Surgical Outcomes and Genomic Insights of Nonclear Cell Renal Cell Carcinoma with Synchronous and Metachronous Nodal Disease.

INTRODUCTION: Oncological outcomes in patients with nonclear cell renal cell carcinoma (non-ccRCC) treated with surgery for locoregional nodal disease (ND) remain incompletely characterized. The objective was to investigate the characteristics and outcomes of non-ccRCC patients treated with lymph node dissection (LND) and salvage-LND (S-LND). METHODS: A total of 1627 patients underwent nephrectomy for nonmetastatic non-ccRCC at Memorial Sloan Kettering Cancer Center between 2007 and 2023. Histology was grouped as papillary, chromophobe, unclassified, and rare subtypes. Retrospective evaluation identified 2.5% (n = 40) of patients with nodal disease at time of nephrectomy (synchronous-ND) and 1.1% (n = 18) with metachronous nodal disease limited to the retroperitoneum (metachronous-ND). Patients' demographics and tumor characteristics were recorded and evaluated by univariate and multivariate cox regression models. Recurrence-free survival (RFS) and overall survival (OS) were estimated by the Kaplan-Meier method. Patients who underwent tumor DNA sequencing during their clinical course were considered for genomic analysis. RESULTS: OS trended toward longer in metachronous-ND (51 vs 105 months; P = .2), though 23% of patients with synchronous-ND were recurrence-free at 45 months median follow-up. In multivariate analysis, rare histologies were associated with decreased OS (P = .030) and metachronous-ND with improved OS (P = .036). RFS and OS after S-LND was 15 and 96 months, respectively. Late onset of metachronous-ND/recurrence was associated with improved OS (P = .008). Genetic alterations in SETD2, TP53, B2M, and FGFR3 were exclusively seen in synchronous-ND, and tumor mutation burden (TMB) was also higher in patients with synchronous-ND (P = .016). CONCLUSIONS: Patients with metachronous-ND tend to have prolonged OS compared to synchronous-ND, but a substantial portion of patients with synchronous-ND still enter a durable disease-free state following LND. S-LND can likewise provide long-term survival, particularly in patients with longer time to metachronous nodal recurrence. Synchronous-ND was associated with SETD2, TP53, and NF2 alteration as well as higher TMB.

Phospholipids with two polyunsaturated fatty acyl tails promote ferroptosis.

Phospholipids containing a single polyunsaturated fatty acyl tail (PL-PUFA1s) are considered the driving force behind ferroptosis, whereas phospholipids with diacyl-PUFA tails (PL-PUFA2s) have been rarely characterized. Dietary lipids modulate ferroptosis, but the mechanisms governing lipid metabolism and ferroptosis sensitivity are not well understood. Our research revealed a significant accumulation of diacyl-PUFA phosphatidylcholines (PC-PUFA2s) following fatty acid or phospholipid treatments, correlating with cancer cell sensitivity to ferroptosis. Depletion of PC-PUFA2s occurred in aging and Huntington's disease brain tissue, linking it to ferroptosis. Notably, PC-PUFA2s interacted with the mitochondrial electron transport chain, generating reactive oxygen species (ROS) for initiating lipid peroxidation. Mitochondria-targeted antioxidants protected cells from PC-PUFA2-induced mitochondrial ROS (mtROS), lipid peroxidation, and cell death. These findings reveal a critical role for PC-PUFA2s in controlling mitochondria homeostasis and ferroptosis in various contexts and explain the ferroptosis-modulating mechanisms of free fatty acids. PC-PUFA2s may serve as diagnostic and therapeutic targets for modulating ferroptosis.

Subtype-selective prenylated isoflavonoids disrupt regulatory drivers of MYCN-amplified cancers.

Transcription factors have proven difficult to target with small molecules because they lack pockets necessary for potent binding. Disruption of protein expression can suppress targets and enable therapeutic intervention. To this end, we developed a drug discovery workflow that incorporates cell-line-selective screening and high-throughput expression profiling followed by regulatory network analysis to identify compounds that suppress regulatory drivers of disease. Applying this approach to neuroblastoma (NBL), we screened bioactive molecules in cell lines representing its MYC-dependent (MYCNA) and mesenchymal (MES) subtypes to identify selective compounds, followed by PLATESeq profiling of treated cells. This revealed compounds that disrupt a sub-network of MYCNA-specific regulatory proteins, resulting in MYCN degradation in vivo. The top hit was isopomiferin, a prenylated isoflavonoid that inhibited casein kinase 2 (CK2) in cells. Isopomiferin and its structural analogs inhibited MYC and MYCN in NBL and lung cancer cells, highlighting the general MYC-inhibiting potential of this unique scaffold.

Ferroptosis inhibition by oleic acid mitigates iron-overload-induced injury.

Iron overload, characterized by accumulation of iron in tissues, induces a multiorgan toxicity whose mechanisms are not fully understood. Using cultured cell lines, Caenorhabditis elegans, and mice, we found that ferroptosis occurs in the context of iron-overload-mediated damage. Exogenous oleic acid protected against iron-overload-toxicity in cell culture and Caenorhabditis elegans by suppressing ferroptosis. In mice, oleic acid protected against FAC-induced liver lipid peroxidation and damage. Oleic acid changed the cellular lipid composition, characterized by decreased levels of polyunsaturated fatty acyl phospholipids and decreased levels of ether-linked phospholipids. The protective effect of oleic acid in cells was attenuated by GW6471 (PPAR-α antagonist), as well as in Caenorhabditis elegans lacking the nuclear hormone receptor NHR-49 (a PPAR-α functional homologue). These results highlight ferroptosis as a driver of iron-overload-mediated damage, which is inhibited by oleic acid. This monounsaturated fatty acid represents a potential therapeutic approach to mitigating organ damage in iron overload individuals.

Kinases Controlling Stability of the Oncogenic MYCN Protein.

We previously identified the natural products isopomiferin and pomiferin as powerful, indirect MYCN-ablating agents. In this work, we expand on their mechanism of action and find that casein kinase 2 (CK2), phosphoinositide 3-kinase (PI3K), checkpoint kinase 1 (CHK1) and serine/threonine protein kinase 38-like (STK38L), as well as STK38, work synchronously to create a field effect that maintains MYCN stability. By systematically inhibiting these kinases, we degraded MYCN and induced cell death. Additionally, we synthesized and tested several simpler and more cost-effective pomiferin analogues, which successfully emulated the compound's MYCN ablating activity. Our work identified and characterized key kinases that can be targeted to interfere with the stability of the MYCN protein in NBL cells, demonstrating the efficacy of an indirect approach to targeting "undruggable" cancer drivers.

Identification of essential sites of lipid peroxidation in ferroptosis.

Ferroptosis, an iron-dependent form of cell death driven by lipid peroxidation, provides a potential treatment avenue for drug-resistant cancers and may play a role in the pathology of some degenerative diseases. Identifying the subcellular membranes essential for ferroptosis and the sequence of their peroxidation will illuminate drug discovery strategies and ferroptosis-relevant disease mechanisms. In this study, we employed fluorescence and stimulated Raman scattering imaging to examine the structure-activity-distribution relationship of ferroptosis-modulating compounds. We found that, although lipid peroxidation in various subcellular membranes can induce ferroptosis, the endoplasmic reticulum (ER) membrane is a key site of lipid peroxidation. Our results suggest an ordered progression model of membrane peroxidation during ferroptosis that accumulates initially in the ER membrane and later in the plasma membrane. Thus, the design of ER-targeted inhibitors and inducers of ferroptosis may be used to optimally control the dynamics of lipid peroxidation in cells undergoing ferroptosis.

Predictors of long-term renal function after kidney surgery for patients with preoperative chronic kidney disease.

INTRODUCTION: We evaluated the trajectory of estimated glomerular filtration rate (eGFR) after kidney surgery in patients with kidney cancer and chronic kidney disease (CKD). METHODS: We identified 1204 consecutive patients in our institutional database with preoperative CKD undergoing partial or radical nephrectomy from 1998-2016. Postoperative eGFR was tracked, with patients censored when receiving dialysis or kidney transplantation. A multivariable mixed-effects models assessed associations between preoperative baseline patient and tumor characteristics, and longitudinal eGFR. The Kaplan-Meier method and multivariable Cox regression were used to estimate overall survival, cancer-specific survival, and cumulative incidence of dialysis. RESULTS: Preoperatively, 892 (74.1%), 271 (22.5%), and 41 (3.4%) patients had CKD stage 3a, 3b, and 4/5, respectively. There were 55 patients dialyzed and 355 deaths (99 from kidney cancer). Median followup was 8.1 years, with 25 781 postoperative eGFR measurements. Factors associated with decreasing eGFR postoperatively included radical nephrectomy, male gender, older age, increased body mass index (BMI), and cardiovascular risk factors. We observed a significant interaction effect between time from surgery and preoperative CKD stage: the eGFR of stage 3a patients improved, while stage ≥3b declined (p<0.001). The two-year and five-year cumulative incidence of dialysis was 1.8% (1.1-2.6%) and 3.1% (2.2-4.2%), respectively. The cumulative incidence of dialysis, with death as a competing event, significantly differed by preoperative CKD stage. CONCLUSIONS: Preoperative CKD stage ≥3b is independently associated with a higher risk of declining renal function, dialysis, and mortality. With careful selection, patients with preoperative CKD withstand kidney surgery with low rates of dialysis.

Patient-derived glioblastoma cultures as a tool for small-molecule drug discovery.

There is a compelling need for new therapeutic strategies for glioblastoma multiforme (GBM). Preclinical target and therapeutic discovery for GBMs is primarily conducted using cell lines grown in serum-containing media, such as U-87 MG, which do not reflect the gene expression profiles of tumors found in GBM patients. To address this lack of representative models, we sought to develop a panel of patient-derived GBM models and characterize their genomic features, using RNA sequencing (RNA-seq) and growth characteristics, both when grown as neurospheres in culture, and grown orthotopically as xenografts in mice. When we compared these with commonly used GBM cell lines in the Cancer Cell Line Encyclopedia (CCLE), we found these patient-derived models to have greater diversity in gene expression and to better correspond to GBMs directly sequenced from patient tumor samples. We also evaluated the potential of these models for targeted therapy, by using the genomic characterization to identify small molecules that inhibit the growth of distinct subsets of GBMs, paving the way for precision medicines for GBM.

The Role of Cytoreductive Nephrectomy for Sarcomatoid Renal Cell Carcinoma: A 29-Year Institutional Experience.

OBJECTIVE: To assess which patients respond best following cytoreductive nephrectomy for renal cell carcinoma (RCC) with sarcomatoid dedifferentiation (sRCC) and whether outcomes are improving over time. METHODS: We identified 562 patients with metastatic RCC treated between 1989 and 2018 with cytoreductive nephrectomy. We reviewed baseline clinical and pathologic characteristics, including the presence of sRCC, and metastatic sites at time of nephrectomy. The primary study endpoint was overall survival (OS). Univariate and multivariate Cox-regression analyses were used to identify significant predictors of OS. RESULTS: The study cohort had 192 sRCC patients, with a median age of 59 years. Frequently involved metastatic locations were lung (n = 115), retroperitoneal nodes (n = 63), and axial skeleton (n = 43). Lung metastasis were more prevalent in clear cell histology (P = .0017) whereas nodal involvement was associated with nonclear cell subtypes (P = .0064). Median follow-up was 14 months. Estimated 2- and 5-year OS were 34.1% and 14.8%, respectively. On multivariate analysis, metastases to the liver (HR = 1.64; 95% CI 1.02-2.63; P = .04), lung (HR = 1.50; 95% CI 1.05-2.14; P = .03), retroperitoneal nodes (HR = 1.52; 95% CI 1.03-2.25; P = 0.04) and nonclear cell histology (HR = 1.61; 95% CI 1.10-2.35; P = .01) were associated with worse OS in the sRCC cohort. CONCLUSION: OS after cytoreductive nephrectomy for sRCC and non-sRCC is improving over time. In patients with sRCC, presentations with unifocal metastasis not involving the liver or lung, clear cell histology and node negative disease have better outcomes following cytoreductive nephrectomy and may yield greater benefit from the procedure.

FINO2 initiates ferroptosis through GPX4 inactivation and iron oxidation.

Ferroptosis is a non-apoptotic form of regulated cell death caused by the failure of the glutathione-dependent lipid-peroxide-scavenging network. FINO2 is an endoperoxide-containing 1,2-dioxolane that can initiate ferroptosis selectively in engineered cancer cells. We investigated the mechanism and structural features necessary for ferroptosis initiation by FINO2. We found that FINO2 requires both an endoperoxide moiety and a nearby hydroxyl head group to initiate ferroptosis. In contrast to previously described ferroptosis inducers, FINO2 does not inhibit system xc- or directly target the reducing enzyme GPX4, as do erastin and RSL3, respectively, nor does it deplete GPX4 protein, as does FIN56. Instead, FINO2 both indirectly inhibits GPX4 enzymatic function and directly oxidizes iron, ultimately causing widespread lipid peroxidation. These findings suggest that endoperoxides such as FINO2 can initiate a multipronged mechanism of ferroptosis.

Copper-Binding Small Molecule Induces Oxidative Stress and Cell-Cycle Arrest in Glioblastoma-Patient-Derived Cells.

Transition metals are essential, but deregulation of their metabolism causes toxicity. Here, we report that the compound NSC319726 binds copper to induce oxidative stress and arrest glioblastoma-patient-derived cells at picomolar concentrations. Pharmacogenomic analysis suggested that NSC319726 and 65 other structural analogs exhibit lethality through metal binding. Although NSC319726 has been reported to function as a zinc ionophore, we report here that this compound binds to copper to arrest cell growth. We generated and validated pharmacogenomic predictions: copper toxicity was substantially inhibited by hypoxia, through an hypoxia-inducible-factor-1α-dependent pathway; copper-bound NSC319726 induced the generation of reactive oxygen species and depletion of deoxyribosyl purines, resulting in cell-cycle arrest. These results suggest that metal-induced DNA damage may be a consequence of exposure to some xenobiotics, therapeutic agents, as well as other causes of copper dysregulation, and reveal a potent mechanism for targeting glioblastomas.

High-Throughput Screening of Patient-Derived Cultures Reveals Potential for Precision Medicine in Glioblastoma.

Identifying drugs for the treatment of glioblastoma (GBM), a rapidly fatal disease, has been challenging. Most screening efforts have been conducted with immortalized cell lines grown with fetal bovine serum, which have little relevance to the genomic features found in GBM patients. Patient-derived neurosphere cultures, while being more physiologically relevant, are difficult to screen and therefore are only used to test a few drug candidates after initial screening efforts. Laminin has been used to generate two-dimensional cell lines from patient tumors, preserving the genomic signature and alleviating some screening hurdles. We present here the first side-by-side comparison of inhibitor sensitivity of laminin and neurosphere-grown patient-derived GBM cell lines and show that both of these culture methods result in the same pattern of inhibitor sensitivity. We used these screening methods to evaluate the dependencies of seven patient-derived cell models: three grown on laminin and four grown as neurospheres, against 56 agents in 17-point dose-response curves in 384-well format in triplicate. This allowed us to establish differential sensitivity of chemotherapeutic agents across the seven patient-derived models. We found that MEK inhibition caused patient-sample-specific growth inhibition and that bortezomib, an FDA-approved proteasome inhibitor, was potently lethal in all patient-derived models. Furthermore, the screening results led us to test the combination of the Bcl-2 inhibitor ABT-263, and the mTOR inhibitor AZD-8055, which we found to be synergistic in a subset of patient-derived GBM models. Thus, we have identified new candidate therapeutics and developed a high-throughput screening system using patient-derived GBM samples.