The Maternal and Infant Environmental Health Riskscape study of perinatal disparities in greater Houston: rationale, study design and participant profiles.

Introduction: The Maternal and Infant Environmental Health Riskscape (MIEHR) Center was established to address the interplay among chemical and non-chemical stressors in the biological, physical, social, and built environments that disproportionately impact perinatal health among Black pregnant people in a large and diverse urban area with documented disparities in the U.S. Methods: The MIEHR cohort is recruiting non-Hispanic Black and non-Hispanic white pregnant people who deliver their infants at major obstetric hospitals in Houston, Texas. At enrollment, all participants are asked to provide urine samples for chemical [metals, cotinine, and polycyclic aromatic hydrocarbons (PAHs)] analyses and blood samples. A subset of the cohort is asked to provide oral and vaginal swabs, and fecal samples. Questionnaire and electronic health record data gather information about residential address history during pregnancy, pregnancy history and prenatal care, sociodemographic and lifestyle factors, experiences of discrimination and stress, and sources of social support. Using information on where a participant lived during their pregnancy, features of their neighborhood environment are characterized. We provide summaries of key individual- and neighborhood-level features of the entire cohort, as well as for Black and white participants separately. Results: Between April 2021 and February 2023, 1,244 pregnant people were recruited. Nearly all participants provided urine samples and slightly less than half provided blood samples. PAH exposure patterns as assessed on 47% of participants thus far showed varying levels depending on metabolite as compared to previous studies. Additionally, analyses suggest differences between Black and white pregnant people in experiences of discrimination, stress, and levels of social support, as well as in neighborhood characteristics. Discussion: Our findings to date highlight racial differences in experiences of discrimination, stress, and levels of support, as well as neighborhood characteristics. Recruitment of the cohort is ongoing and additional neighborhood metrics are being constructed. Biospecimens will be analyzed for metals and PAH metabolites (urine samples), miRNAs (plasma samples) and the microbiome (oral swabs). Once enrollment ends, formal assessments are planned to elucidate individual- and neighborhood-level features in the environmental riskscape that contribute to Black-White disparities in perinatal health.

"Holy cow, where do I sign up?" Attitudes of Military Veterans toward Epigenomic Biomarker Toxic Exposure Testing.

Background: With the signing of the PACT Act in 2022, there is great interest and investment in studying toxic exposures encountered during military service. One way to address this is through the identification of epigenomic biomarkers associated with exposures. There is increasing evidence suggesting that exposure to toxic substances may result in alterations to DNA methylation and resultant gene expression. These epigenomic changes may lead to adverse health effects for exposed individuals and their offspring. While the development of epigenomic biomarkers for exposures could facilitate understanding of these exposure-related health effects, such testing could also provide unwanted information. Objectives: Explore Veterans' attitudes toward epigenomic biomarker research and the potential to test for past exposures that could pose intergenerational risk. Methods: Semi-structured interviews with Veterans (n=22) who experienced potentially harmful exposures during their military service. Results: Twenty Veterans said they would hypothetically want to receive epigenomic information related to their toxic exposures and potential health impacts as part of a research study. Veterans identified nine potential benefits of this research, including promoting insights concerning intergenerational health, identification of early health interventions to mitigate the impact of exposures, and additional knowledge or explanation for their experiences. At the same time, 16 participants noted potential risks, including psychological distress in response to results, concerns about receiving non-actionable, uncertain, or inaccurate results, and issues related to privacy and discrimination. Ten participants also identified at least one condition in their children that they thought could be related to their exposure and most said they would be interested in receiving research results related to their children's and grandchildren's risk of developing a health condition associated with their exposure. Discussion: Results suggest that Veterans might welcome benefits of epigenomic research related to military exposures yet have some concerns about potential negative impacts.

Lysine Demethylase 4A is a Centrosome Associated Protein Required for Centrosome Integrity and Genomic Stability.

Centrosomes play a fundamental role in nucleating and organizing microtubules in the cell and are vital for faithful chromosome segregation and maintenance of genomic stability. Loss of structural or functional integrity of centrosomes causes genomic instability and is a driver of oncogenesis. The lysine demethylase 4A (KDM4A) is an epigenetic 'eraser' of chromatin methyl marks, which we show also localizes to the centrosome with single molecule resolution. We additionally discovered KDM4A demethylase enzymatic activity is required to maintain centrosome homeostasis, and is required for centrosome integrity, a new functionality unlinked to altered expression of genes regulating centrosome number. We find rather, that KDM4A interacts with both mother and daughter centriolar proteins to localize to the centrosome in all stages of mitosis. Loss of KDM4A results in supernumerary centrosomes and accrual of chromosome segregation errors including chromatin bridges and micronuclei, markers of genomic instability. In summary, these data highlight a novel role for an epigenetic 'eraser' regulating centrosome integrity, mitotic fidelity, and genomic stability at the centrosome.

TGFß signaling links early life endocrine-disrupting chemicals exposure to suppression of nucleotide excision repair in rat myometrial stem cells.

Environmental exposure to endocrine-disrupting chemicals (EDCs) is linked to the development of uterine fibroids (UFs) in women. UFs, non-cancerous tumors, are thought to originate from abnormal myometrial stem cells (MMSCs). Defective DNA repair capacity may contribute to the emergence of mutations that promote tumor growth. The multifunctional cytokine TGFß1 is associated with UF progression and DNA damage repair pathways. To investigate the impact of EDC exposure on TGFß1 and nucleotide excision repair (NER) pathways, we isolated MMSCs from 5-month-old Eker rats exposed neonatally to diethylstilbestrol (DES), an EDC, or to vehicle (VEH). EDC-MMSCs exhibited overactivated TGFß1 signaling and reduced mRNA and protein levels of NER pathway components compared to VEH-MMSCs. EDC-MMSCs also demonstrated impaired NER capacity. Exposing VEH-MMSCs to TGFß1 decreased NER capacity while inhibiting TGFß signaling in EDC-MMSCs restored it. RNA-seq analysis and further validation revealed decreased expression of Uvrag, a tumor suppressor gene involved in DNA damage recognition, in VEH-MMSCs treated with TGFß1, but increased expression in EDC-MMSCs after TGFß signaling inhibition. Overall, we demonstrated that the overactivation of the TGFß pathway links early life exposure to EDCs with impaired NER capacity, which would lead to increased genetic instability, arise of mutations, and fibroid tumorigenesis. We demonstrated that the overactivation of the TGFß pathway links early life exposure to EDCs with impaired NER capacity, which would lead to increased fibroid incidence.

TGFß signaling links early-life endocrine-disrupting chemicals exposure to suppression of nucleotide excision repair in rat myometrial stem cells.

Environmental exposure to endocrine-disrupting chemicals (EDCs) is linked to the development of uterine fibroids (UFs) in women. UFs, non-cancerous tumors, are thought to originate from abnormal myometrial stem cells (MMSCs). Defective DNA repair capacity may contribute to the emergence of mutations that promote tumor growth. The multifunctional cytokine TGFß1 is associated with UF progression and DNA damage repair pathways. To investigate the impact of EDC exposure on TGFß1 and nucleotide excision repair (NER) pathways, we isolated MMSCs from 5-months old Eker rats exposed neonatally to Diethylstilbestrol (DES), an EDC, or to vehicle (VEH). EDC-MMSCs exhibited overactivated TGFß1 signaling and reduced mRNA and protein levels of NER pathway components compared to VEH-MMSCs. EDC-MMSCs also demonstrated impaired NER capacity. Exposing VEH-MMSCs to TGFß1 decreased NER capacity while inhibiting TGFß signaling in EDC-MMSCs restored it. RNA-seq analysis and further validation revealed decreased expression of Uvrag, a tumor suppressor gene involved in DNA damage recognition, in VEH-MMSCs treated with TGFß1, but increased expression in EDC-MMSCs after TGFß signaling inhibition. Overall, we demonstrated that the overactivation of the TGFß pathway links early-life exposure to EDCs with impaired NER capacity, which would lead to increased genetic instability, arise of mutations, and fibroid tumorigenesis. We demonstrated that the overactivation of the TGFß pathway links early-life exposure to EDCs with impaired NER capacity, which would lead to increased fibroid incidence.

SMARCB1 regulates the hypoxic stress response in sickle cell trait.

Renal medullary carcinoma (RMC) is an aggressive kidney cancer that almost exclusively develops in individuals with sickle cell trait (SCT) and is always characterized by loss of the tumor suppressor SMARCB1. Because renal ischemia induced by red blood cell sickling exacerbates chronic renal medullary hypoxia in vivo, we investigated whether the loss of SMARCB1 confers a survival advantage under the setting of SCT. Hypoxic stress, which naturally occurs within the renal medulla, is elevated under the setting of SCT. Our findings showed that hypoxia-induced SMARCB1 degradation protected renal cells from hypoxic stress. SMARCB1 wild-type renal tumors exhibited lower levels of SMARCB1 and more aggressive growth in mice harboring the SCT mutation in human hemoglobin A (HbA) than in control mice harboring wild-type human HbA. Consistent with established clinical observations, SMARCB1-null renal tumors were refractory to hypoxia-inducing therapeutic inhibition of angiogenesis. Further, reconstitution of SMARCB1 restored renal tumor sensitivity to hypoxic stress in vitro and in vivo. Together, our results demonstrate a physiological role for SMARCB1 degradation in response to hypoxic stress, connect the renal medullary hypoxia induced by SCT with an increased risk of SMARCB1-negative RMC, and shed light into the mechanisms mediating the resistance of SMARCB1-null renal tumors against angiogenesis inhibition therapies.

Neddylation inhibition sensitises renal medullary carcinoma tumours to platinum chemotherapy.

BACKGROUND: Renal medullary carcinoma (RMC) is a highly aggressive cancer in need of new therapeutic strategies. The neddylation pathway can protect cells from DNA damage induced by the platinum-based chemotherapy used in RMC. We investigated if neddylation inhibition with pevonedistat will synergistically enhance antitumour effects of platinum-based chemotherapy in RMC. METHODS: We evaluated the IC50 concentrations of the neddylation-activating enzyme inhibitor pevonedistat in vitro in RMC cell lines. Bliss synergy scores were calculated using growth inhibition assays following treatment with varying concentrations of pevonedistat and carboplatin. Protein expression was assessed by western blot and immunofluorescence assays. The efficacy of pevonedistat alone or in combination with platinum-based chemotherapy was evaluated in vivo in platinum-naïve and platinum-experienced patient-derived xenograft (PDX) models of RMC. RESULTS: The RMC cell lines demonstrated IC50 concentrations of pevonedistat below the maximum tolerated dose in humans. When combined with carboplatin, pevonedistat demonstrated a significant in vitro synergistic effect. Treatment with carboplatin alone increased nuclear ERCC1 levels used to repair the interstrand crosslinks induced by platinum salts. Conversely, the addition of pevonedistat to carboplatin led to p53 upregulation resulting in FANCD2 suppression and reduced nuclear ERCC1 levels. The addition of pevonedistat to platinum-based chemotherapy significantly inhibited tumour growth in both platinum-naïve and platinum-experienced PDX models of RMC (p < .01). CONCLUSIONS: Our results suggest that pevonedistat synergises with carboplatin to inhibit RMC cell and tumour growth through inhibition of DNA damage repair. These findings support the development of a clinical trial combining pevonedistat with platinum-based chemotherapy for RMC.

Association of High-Intensity Exercise with Renal Medullary Carcinoma in Individuals with Sickle Cell Trait: Clinical Observations and Experimental Animal Studies.

Renal medullary carcinoma (RMC) is a lethal malignancy affecting individuals with sickle hemoglobinopathies. Currently, no modifiable risk factors are known. We aimed to determine whether high-intensity exercise is a risk factor for RMC in individuals with sickle cell trait (SCT). We used multiple approaches to triangulate our conclusion. First, a case-control study was conducted at a single tertiary-care facility. Consecutive patients with RMC were compared to matched controls with similarly advanced genitourinary malignancies in a 1:2 ratio and compared on rates of physical activity and anthropometric measures, including skeletal muscle surface area. Next, we compared the rate of military service among our RMC patients to a similarly aged population of black individuals with SCT in the U.S. Further, we used genetically engineered mouse models of SCT to study the impact of exercise on renal medullary hypoxia. Compared with matched controls, patients with RMC reported higher physical activity and had higher skeletal muscle surface area. A higher proportion of patients with RMC reported military service than expected compared to the similarly-aged population of black individuals with SCT. When exposed to high-intensity exercise, mice with SCT demonstrated significantly higher renal medulla hypoxia compared to wild-type controls. These data suggest high-intensity exercise is the first modifiable risk factor for RMC in individuals with SCT.

A cytoskeletal function for PBRM1 reading methylated microtubules.

Epigenetic effectors "read" marks "written" on chromatin to regulate function and fidelity of the genome. Here, we show that this coordinated read-write activity of the epigenetic machinery extends to the cytoskeleton, with PBRM1 in the PBAF chromatin remodeling complex reading microtubule methyl marks written by the SETD2 histone methyltransferase. PBRM1 binds SETD2 methyl marks via BAH domains, recruiting PBAF components to the mitotic spindle. This read-write activity was required for normal mitosis: Loss of SETD2 methylation or pathogenic BAH domain mutations disrupt PBRM1 microtubule binding and PBAF recruitment and cause genomic instability. These data reveal PBRM1 functions beyond chromatin remodeling with domains that allow it to integrate chromatin and cytoskeletal activity via its acetyl-binding BD and methyl-binding BAH domains, respectively. Conserved coordinated activity of the epigenetic machinery on the cytoskeleton opens a previously unknown window into how chromatin remodeler defects can drive disease via both epigenetic and cytoskeletal dysfunction.

Epigenetic response to hyperoxia in the neonatal lung is sexually dimorphic.

Sex as a biological variable plays a critical role both during lung development and in modulating postnatal hyperoxic lung injury and repair. The molecular mechanisms behind these sex-specific differences need to be elucidated. Our objective was to determine if the neonatal lung epigenomic landscape reconfiguration has profound effects on gene expression and could underlie sex-biased differences in protection from or susceptibility to diseases. Neonatal male and female mice (C57BL/6) were exposed to hyperoxia (95% FiO, PND 1-5: saccular stage) or room air and euthanized on PND 7 and 21. Pulmonary gene expression was studied using RNA-seq on Illumina HiSeq 2500 platform and quantified. Epigenomic landscape was assessed using Chromatin Immunoprecipitation (ChIP-Seq) of the H3K27ac histone modification mark, associated with active genes, enhancers, and super-enhancers. These data were then integrated, pathways identified and validated. Sex-biased epigenetic modulation of gene expression leads to differential regulation of biological processes in the developing lung at baseline and after exposure to hyperoxia. The female lung exhibits a more robust epigenomic response for the H3K27ac mark in response to hyperoxia. Epigenomic changes distribute over genomic and epigenomic domains in a sex-specific manner. The differential epigenomic responses also enrich for key transcription regulators crucial for lung development. In addition, by utilizing H3K27ac as the target epigenomic change we were also able to identify new epigenomic reprogramming at super-enhancers. Finally, we report for the first time that the upregulation of p21 (Cdkn1a) in the injured neonatal lung could be mediated through gain of H3K27ac. These data demonstrate that modulation of transcription via epigenomic landscape alterations may contribute to the sex-specific differences in preterm neonatal hyperoxic lung injury and repair.

Molecular hallmarks of renal medullary carcinoma: more to c-MYC than meets the eye.

Renal medullary carcinoma (RMC) is a lethal disease that predominantly afflicts young individuals with sickle cell trait. Our recently reported molecular profiling of primary untreated RMC tissues elucidated distinct genomic and immune hallmarks of RMC, and identified MYC-induced replication stress as a targetable vulnerability for this disease.

Comprehensive Molecular Characterization Identifies Distinct Genomic and Immune Hallmarks of Renal Medullary Carcinoma.

Renal medullary carcinoma (RMC) is a highly lethal malignancy that mainly afflicts young individuals of African descent and is resistant to all targeted agents used to treat other renal cell carcinomas. Comprehensive genomic and transcriptomic profiling of untreated primary RMC tissues was performed to elucidate the molecular landscape of these tumors. We found that RMC was characterized by high replication stress and an abundance of focal copy-number alterations associated with activation of the stimulator of the cyclic GMP-AMP synthase interferon genes (cGAS-STING) innate immune pathway. Replication stress conferred a therapeutic vulnerability to drugs targeting DNA-damage repair pathways. Elucidation of these previously unknown RMC hallmarks paves the way to new clinical trials for this rare but highly lethal malignancy.

p53 Is a Master Regulator of Proteostasis in SMARCB1-Deficient Malignant Rhabdoid Tumors.

Alterations in chromatin remodeling genes have been increasingly implicated in human oncogenesis. Specifically, the biallelic inactivation of the SWI/SNF subunit SMARCB1 results in the emergence of extremely aggressive pediatric malignancies. Here, we developed embryonic mosaic mouse models of malignant rhabdoid tumors (MRTs) that faithfully recapitulate the clinical-pathological features of the human disease. We demonstrated that SMARCB1-deficient malignancies exhibit dramatic activation of the unfolded protein response (UPR) and ER stress response via a genetically intact MYC-p19ARF-p53 axis. As a consequence, these tumors display an exquisite sensitivity to agents inducing proteotoxic stress and inhibition of the autophagic machinery. In conclusion, our findings provide a rationale for drug repositioning trials investigating combinations of agents targeting the UPR and autophagy in SMARCB1-deficient MRTs.

CARM1 methylates MED12 to regulate its RNA-binding ability.

The coactivator-associated arginine methyltransferase (CARM1) functions as a regulator of transcription by methylating a diverse array of substrates. To broaden our understanding of CARM1's mechanistic actions, we sought to identify additional substrates for this enzyme. To do this, we generated CARM1 substrate motif antibodies, and used immunoprecipitation coupled with mass spectrometry to identify cellular targets of CARM1, including mediator complex subunit 12 (MED12) and the lysine methyltransferase KMT2D. Both of these proteins are implicated in enhancer function. We identified the major CARM1-mediated MED12 methylation site as arginine 1899 (R1899), which interacts with the Tudor domain-containing effector molecule, TDRD3. Chromatin immunoprecipitation-seq studies revealed that CARM1 and the methyl mark it deposits are tightly associated with ERα-specific enhancers and positively modulate transcription of estrogen-regulated genes. In addition, we showed that the methylation of MED12, at the R1899 site, and the recruitment of TDRD3 by this methylated motif are critical for the ability of MED12 to interact with activating noncoding RNAs.

SETD2 Haploinsufficiency for Microtubule Methylation Is an Early Driver of Genomic Instability in Renal Cell Carcinoma.

Loss of the short arm of chromosome 3 (3p) occurs early in >95% of clear cell renal cell carcinoma (ccRCC). Nearly ubiquitous 3p loss in ccRCC suggests haploinsufficiency for 3p tumor suppressors as early drivers of tumorigenesis. We previously reported methyltransferase SETD2, which trimethylates H3 histones on lysine 36 (H3K36me3) and is located in the 3p deletion, to also trimethylate microtubules on lysine 40 (αTubK40me3) during mitosis, with αTubK40me3 required for genomic stability. We now show that monoallelic, Setd2-deficient cells retaining H3K36me3, but not αTubK40me3, exhibit a dramatic increase in mitotic defects and micronuclei count, with increased viability compared with biallelic loss. In SETD2-inactivated human kidney cells, rescue with a pathogenic SETD2 mutant deficient for microtubule (αTubK40me3), but not histone (H3K36me3) methylation, replicated this phenotype. Genomic instability (micronuclei) was also a hallmark of patient-derived cells from ccRCC. These data show that the SETD2 tumor suppressor displays a haploinsufficiency phenotype disproportionately impacting microtubule methylation and serves as an early driver of genomic instability.Significance: Loss of a single allele of a chromatin modifier plays a role in promoting oncogenesis, underscoring the growing relevance of tumor suppressor haploinsufficiency in tumorigenesis. Cancer Res; 78(12); 3135-46. ©2018 AACR.

Redox Regulation of Homeostasis and Proteostasis in Peroxisomes.

Peroxisomes are highly dynamic intracellular organelles involved in a variety of metabolic functions essential for the metabolism of long-chain fatty acids, d-amino acids, and many polyamines. A byproduct of peroxisomal metabolism is the generation, and subsequent detoxification, of reactive oxygen and nitrogen species, particularly hydrogen peroxide (H2O2). Because of its relatively low reactivity (as a mild oxidant), H2O2 has a comparatively long intracellular half-life and a high diffusion rate, all of which makes H2O2 an efficient signaling molecule. Peroxisomes also have intricate connections to mitochondria, and both organelles appear to play important roles in regulating redox signaling pathways. Peroxisomal proteins are also subject to oxidative modification and inactivation by the reactive oxygen and nitrogen species they generate, but the peroxisomal LonP2 protease can selectively remove such oxidatively damaged proteins, thus prolonging the useful lifespan of the organelle. Peroxisomal homeostasis must adapt to the metabolic state of the cell, by a combination of peroxisome proliferation, the removal of excess or badly damaged organelles by autophagy (pexophagy), as well as by processes of peroxisome inheritance and motility. More recently the tumor suppressors ataxia telangiectasia mutate (ATM) and tuberous sclerosis complex (TSC), which regulate mTORC1 signaling, have been found to regulate pexophagy in response to variable levels of certain reactive oxygen and nitrogen species. It is now clear that any significant loss of peroxisome homeostasis can have devastating physiological consequences. Peroxisome dysregulation has been implicated in several metabolic diseases, and increasing evidence highlights the important role of diminished peroxisomal functions in aging processes.

HNF1B Loss Exacerbates the Development of Chromophobe Renal Cell Carcinomas.

Chromophobe renal cell carcinoma (ChRCC) is characterized by major changes in chromosomal copy number (CN). No model is available to precisely elucidate the molecular drivers of this tumor type. HNF1B is a master regulator of gene expression. Here, we report that the transcription factor HNF1B is downregulated in the majority of ChRCC and that the magnitude of HNF1B loss is unique to ChRCC. We also observed a strong correlation between reduced HNF1B expression and aneuploidy in ChRCC patients. In murine embryonic fibroblasts or ACHN cells, HNF1B deficiency reduced expression of the spindle checkpoint proteins MAD2L1 and BUB1B, and the cell-cycle checkpoint proteins RB1 and p27. Furthermore, it altered the chromatin accessibility of Mad2l1, Bub1b, and Rb1 genes and triggered aneuploidy development. Analysis of The Cancer Genome Atlas database revealed TP53 mutations in 33% of ChRCC where HNF1B expression was repressed. In clinical specimens, combining HNF1B loss with TP53 mutation produced an association with poor patient prognosis. In cells, combining HNF1B loss and TP53 mutation increased cell proliferation and aneuploidy. Our results show how HNF1B loss leads to abnormal mitotic protein regulation and induction of aneuploidy. We propose that coordinate loss of HNF1B and TP53 may enhance cellular survival and confer an aggressive phenotype in ChRCC. Cancer Res; 77(19); 5313-26. ©2017 AACR.

Characterizing properties of non-estrogenic substituted bisphenol analogs using high throughput microscopy and image analysis.

Animal studies have linked the estrogenic properties of bisphenol A (BPA) to adverse effects on the endocrine system. Because of concerns for similar effects in humans, there is a desire to replace BPA in consumer products, and a search for BPA replacements that lack endocrine-disrupting bioactivity is ongoing. We used multiple cell-based models, including an established multi-parametric, high throughput microscopy-based platform that incorporates engineered HeLa cell lines with visible ERα- or ERß-regulated transcription loci, to discriminate the estrogen-like and androgen-like properties of previously uncharacterized substituted bisphenol derivatives and hydroquinone. As expected, BPA induced 70-80% of the estrogen-like activity via ERα and ERß compared to E2 in the HeLa prolactin array cell line. 2,2' BPA, Bisguaiacol F, CHDM 4-hydroxybuyl acrylate, hydroquinone, and TM modified variants of BPF showed very limited estrogen-like or androgen-like activity (< 10% of that observed with the control compounds). Interestingly, TM-BFP and CHDM 4-hydroxybuyl acrylate, but not their derivatives, demonstrated evidence of anti-estrogenic and anti-androgenic activity. Our findings indicate that Bisguaiacol F, TM-BFP-ER and TM-BPF-DGE demonstrate low potential for affecting estrogenic or androgenic endocrine activity. This suggest that the tested compounds could be suitable commercially viable alternatives to BPA.

Renal Medullary Carcinoma: Establishing Standards in Practice.

Although renal medullary carcinoma (RMC) is a rare subtype of kidney cancer, it is particularly devastating in that it is nearly uniformly lethal. No established guidelines exist for the diagnosis and management of RMC. In April 2016, a panel of experts developed clinical guidelines on the basis of a literature review and consensus statements. The goal was to propose recommendations for standardized diagnostic and management approaches and to establish an international clinical registry and biorepository for RMC. Published data are limited to case reports and small retrospective reviews. The RMC Working Group prepared recommendations to inform providers and patients faced with a low level of medical evidence. The diagnosis of RMC should be considered in all patients younger than 50 years with poorly differentiated carcinoma that arises from the renal medulla. These patients should be tested for sickle cell hemoglobinopathies, and if positive, SMARCB1/INI1 loss should be confirmed by immunohistochemistry. The majority of patients with RMC are diagnosed with metastatic disease. Upfront radical nephrectomy should be considered in patients with good performance status and low metastatic burden or after response to systemic therapy. Currently, cytotoxic, platinum-based chemotherapy provides the best, albeit brief, palliative clinical benefit. Vascular endothelial growth factor-directed therapies and mammalian target of rapamycin inhibitors are ineffective in RMC as monotherapy. Therapeutic trials of novel agents are now available for RMC, and every effort should be made to enroll patients in clinical studies.