A novel uterine leiomyoma subtype exhibits NRF2 activation and mutations in genes associated with neddylation of the Cullin 3-RING E3 ligase

Chromatin state origins of uterine leiomyoma

Aberrations in the regulatory genome play a pivotal role in population-level disease predisposition. Annotation of the regulatory regions using appropriate primary tissues - instead of cell lines affected by selection and other confounding factors - could shed new light into mechanisms underlying common conditions. We test this approach in uterine leiomyomas, highly prevalent benign neoplasms of the myometrium, by creating 15-state chromatin annotations for myometrium and uterine leiomyomas. Integration with RNA-seq, ATAC-seq, HiChIP and methylation data enables us to compare the epigenomes of myometrium and ULs with distinct driver mutations, highlighting the role of bivalent regions in the neoplastic process. Subsequently, a genome wide association study meta-analysis is performed, using three different cohorts. Disease association loci are enriched at active chromatin, especially at enhancers, and harbor tumor- and driver mutation-specific chromatin states. At SATB2 locus we show the effect of the risk genotype already in the normal tissue. Integration of genome-wide association studies and deep regulatory genomics data from the correct tissue type represents a powerful approach in understanding population-level disease predisposition.

Health position paper and redox perspectives - Bench to bedside transition for pharmacological regulation of NRF2 in noncommunicable diseases

Nuclear factor erythroid 2-related factor 2 (NRF2) is a redox-activated transcription factor regulating cellular defense against oxidative stress, thereby playing a pivotal role in maintaining cellular homeostasis. Its dysregulation is implicated in the progression of a wide array of human diseases, making NRF2 a compelling target for therapeutic interventions. However, challenges persist in drug discovery and safe targeting of NRF2, as unresolved questions remain especially regarding its context-specific role in diseases and off-target effects. This comprehensive review discusses the dualistic role of NRF2 in disease pathophysiology, covering its protective and/or destructive roles in autoimmune, respiratory, cardiovascular, and metabolic diseases, as well as diseases of the digestive system and cancer. Additionally, we also review the development of drugs that either activate or inhibit NRF2, discuss main barriers in translating NRF2-based therapies from bench to bedside, and consider the ways to monitor NRF2 activation in vivo.

Activation of FGFR genes by genetic and epigenetic alterations in uterine leiomyomas

BACKGROUND

Fibroblast growth factor 1-4 (FGFR1-4) are well-known oncogenic drivers in many cancer types. Here, we studied the role of FGFRs in uterine leiomyoma (UL) that is a benign neoplasm arising from the myometrium and the most common tumour in women. Although ULs can be classified to molecular subtypes based on genetic drivers, potential secondary drivers are not well characterised.

METHODS

We performed mutation analysis of RNA-sequencing data of ULs, followed by screening of FGFR alterations in our Finnish (n = 2677) and Swedish (n = 372) UL collections, utilising Sanger-, next-generation and Nanopore sequencing and SNP array data. The role of FGFR genes in UL predisposition was examined by GWAS.

RESULTS

We identified FGFR activation in a subset of ULs on both genetic and epigenetic levels. In addition to single-nucleotide mutations in FGFR1/2, we detected an FGFR2-ERC1 fusion gene, FGFR1 gains and hypomethylation of regulatory regions of FGFR2/3. FGFR alterations were enriched in molecularly similar HMGA2, HMGA1 and PLAG1 UL subtypes. We also unveil a UL predisposing variant upstream of FGFR4 associated with increased expression in both normal myometrium and ULs.

CONCLUSIONS

Our results establish the role of FGFR signalling in the genesis of UL.

Detection of exon2-MED12 mutations in uterine leiomyomas from Syrian patients

Uterine leiomyomas (uLMs) are the most prevalent benign tumors of the female reproductive system. MED12 is one of the mediator complex subunits that has been implicated in uLMs pathogenesis. Somatic mutations in exon2-MED12 have been found in ~ 70% of uLMs. In this study, we investigated the status of exon2-MED12 in uLMs from Syrian patients. Sixteen leiomyomas from nine patients were assessed. Genomic DNA was isolated from tumors and exon2-MED12 was amplified by PCR and sequenced. Three specimens showed in frame point mutations consisted of missense substitutions in codon 44 (c.130). A novel insertion in codon 35 (c.103insG) was detected in one of the mutated cases and is expected to cause a frameshift in translation and an altered or truncated product. Some of the wild-type uLMs were collected from the same uteri that revealed mutations, which emphasizes the individuality of the uLM lesions and highlights the complexity of uLMs pathogenesis. The study is the first report from Syria on the topic and the second from the Arab world. It indicates genetic heterogeneity and independent clonal origin of the somatic mutations in exon2-MED12. In wild-type uLMs where exon2-MED12 mutations are absent, other players are in place and should be investigated.

Clinical and molecular risk factors for repeat interventions due to symptomatic uterine leiomyomas

BACKGROUND

Repeat leiomyoma occurrence or even reintervention is common after myomectomy. Little is known about the factors related to repeat interventions.

OBJECTIVE

This study aimed to determine the frequency of leiomyoma-related reintervention after an initial laparoscopic or abdominal myomectomy and to analyze both clinical and molecular risk factors for reinterventions. Another objective was to define the frequency of clonally related tumors from repeat operations.

STUDY DESIGN

This retrospective cohort study included 234 women who had undergone laparoscopic or abdominal myomectomy in 2009 to 2014. Information on repeat leiomyoma-related interventions as well as on other clinical factors was collected from medical records after a median follow-up time of 11.4 years (range 7.9-13.8 years) after the index procedure. The effect of clinical risk factors on the risk of reintervention was analyzed by the Kaplan-Meier estimator and the Cox proportional hazards model. For molecular analyses, we examined the mutation profiles of 133 formalin-fixed paraffin-embedded leiomyoma samples from 33 patients with repeat operations. We screened the tumors for the 3 primary leiomyoma driver alterations-mediator complex subunit 12 mutations, high mobility group AT-hook 2 overexpression, and fumarate hydratase-deficiency-utilizing Sanger sequencing and immunohistochemistry. To further assess the clonal relationship of the tumors, we executed whole-exome sequencing for 52 leiomyomas from 21 patients who exhibited the same driver alteration in tumors obtained from multiple procedures.

RESULTS

Reintervention rate at 11.4 years after myomectomy was 20% (46/234). Number of leiomyomas removed at the index myomectomy was a risk factor (hazard ratio 1.21; 95% confidence interval 1.09-1.34). Age at index myomectomy (hazard ratio 0.94; 95% confidence interval 0.89-0.99) and postoperative parity (hazard ratio 0.23; 95% confidence interval 0.09-0.60) were protective factors. Molecular characterization of tumors from index and nonindex operations confirmed a clonal relationship of the tumors in 3/33 (9%) patients. None of the leiomyomas harboring a mediator complex subunit 12 mutation-the most common leiomyoma driver-were confirmed clonally related. Fumarate hydratase-deficiency was detected in repeat leiomyomas from 3/33 (9%) patients. All these patients harbored a germline fumarate hydratase mutation, which is distinctive for the hereditary leiomyomatosis and renal cell cancer syndrome. Finally, we identified 3 (3/33; 9%) patients with 2 tumors each displaying somatic mutations in a recently identified novel leiomyoma driver gene, YEATS domain-containing protein 4. All YEATS domain-containing protein 4 mutations were different and thus the tumors were not clonally related.

CONCLUSION

Our study shows that reintervention is common after surgical myomectomy. Uterine leiomyomas typically develop independently, but some share a clonal origin. Repeat leiomyoma occurrence may be due to genetic predisposition, such as a germline fumarate hydratase mutation. Distinct somatic YEATS domain-containing protein 4 mutations identified in multiple leiomyomas from the same patient indicate a possible role for YEATS domain-containing protein 4 in repeat leiomyomas.

The Complex Roles of Redox and Antioxidant Biology in Cancer

Redox reactions control fundamental biochemical processes, including energy production, metabolism, respiration, detoxification, and signal transduction. Cancer cells, due to their generally active metabolism for sustained proliferation, produce high levels of reactive oxygen species (ROS) compared to normal cells and are equipped with antioxidant defense systems to counteract the detrimental effects of ROS to maintain redox homeostasis. The KEAP1-NRF2 system plays a major role in sensing and regulating endogenous antioxidant defenses in both normal and cancer cells, creating a bivalent contribution of NRF2 to cancer prevention and therapy. Cancer cells hijack the NRF2-dependent antioxidant program and exploit a very unique metabolism as a trade-off for enhanced antioxidant capacity. This work provides an overview of redox metabolism in cancer cells, highlighting the role of the KEAP1-NRF2 system, selenoproteins, sulfur metabolism, heme/iron metabolism, and antioxidants. Finally, we describe therapeutic approaches that can be leveraged to target redox metabolism in cancer.

Quality of life after myomectomy according to the surgical approach and MED12 mutation status

OBJECTIVE

Molecular status of uterine leiomyomas has been shown to affect both tumor characteristics and treatment response. Mutations in mediator complex subunit 12 (MED12), the most prevalent alterations in leiomyomas, are associated with tumor size and number of leiomyomas. Myomectomy can be performed by laparoscopy or by open abdominal surgery, depending on the size and number of leiomyomas removed. The aim of this study was to examine the association between MED12 mutation status and surgical approach of myomectomy. We also evaluated myomectomy patients' quality of life after laparoscopic or abdominal surgery and according to the MED12 mutation status.

STUDY DESIGN

The prospective cohort study included 104 women who underwent laparoscopic or abdominal myomectomy at the Helsinki University Hospital during 2015-2019. Patients filled in the validated Uterine Fibroid Symptom and Quality of Life (UFS-QOL) questionnaire before the operation and 6 and 12 months after the operation. Medical records were reviewed to collect clinical data. Leiomyoma tissue samples were collected and screened for MED12 mutations.

RESULTS

Patients undergoing abdominal myomectomy had larger and more numerous leiomyomas compared to patients with laparoscopic myomectomy (10 cm vs 7.4 cm, p < 0.001 and 3 vs 1 leiomyomas, p < 0.001, respectively). A mean change of over 20 points was seen in UFS-QOL scores at 6 months after both laparoscopic and abdominal myomectomy (p < 0.001). MED12 mutations were detected in 178/242 (74 %) of leiomyomas. Of the patients, 45/97 (46 %) had only MED12 positive leiomyomas, while 39/97 (40 %) had only MED12 wild type leiomyomas. The number of leiomyomas removed was higher among patients with MED12 positive leiomyomas than in patients with MED12 wild type tumors (p < 0.001). Laparoscopic approach was equally common in both groups (62 % and 64 %), and there was no statistically significant difference in the UFS-QOL scores.

CONCLUSION

Both laparoscopic and abdominal myomectomy significantly improved the quality of life. While MED12 mutations were related with multiple leiomyomas and therefore potentially generated a greater leiomyoma burden, they were not associated with the surgical approach. Pre- and postoperative quality of life was comparable between patients regardless of MED12 status.

Role of AKR1B10 in inflammatory diseases

Inflammation is an important pathophysiological process in many diseases; it has beneficial and harmful effects. When exposed to various stimuli, the body triggers an inflammatory response to eliminate invaded pathogens and damaged tissues to maintain homeostasis. However, uncontrollable persistent or excessive inflammatory responses may damage tissues and induce various diseases, such as metabolic diseases (e.g. diabetes), autoimmune diseases, nervous system-related diseases, digestive system-related diseases, and even tumours. Aldo-keto reductase 1B10 (AKR1B10) is an important player in the development and progression of multiple diseases, such as tumours and inflammatory diseases. AKR1B10 is upregulated in solid tumours, such as hepatocellular carcinoma (HCC), non-small cell lung carcinoma, and breast cancer, and is a reliable serum marker. However, information on the role of AKR1B10 in inflammation is limited. In this study, we summarized the role of AKR1B10 in inflammatory diseases, including its expression, functional contribution to inflammatory responses, and regulation of signalling pathways related to inflammation. We also discussed the role of AKR1B10 in glucose and lipid metabolism and oxidative stress. This study provides novel information and increases the understanding of clinical inflammatory diseases.

MSC-derived small extracellular vesicles mitigate diabetic retinopathy by stabilizing Nrf2 through miR-143-3p-mediated inhibition of neddylation

Diabetic retinopathy (DR) is a highly hazardous and widespread complication of diabetes mellitus (DM). The accumulated reactive oxygen species (ROS) play a central role in DR development. The aim of this research was to examine the impact and mechanisms of mesenchymal stem cell (MSC)-derived small extracellular vesicles (sEV) on regulating ROS and retinal damage in DR. Intravitreal injection of sEV inhibited Cullin3 neddylation, stabilized Nrf2, decreased ROS, reduced retinal inflammation, suppressed Müller gliosis, and mitigated DR. Based on MSC-sEV miRNA sequencing, bioinformatics software, and dual-luciferase reporter assay, miR-143-3p was identified to be the key effector for MSC-sEV's role in regulating neural precursor cell expressed developmentally down-regulated 8 (NEDD8)-mediated neddylation. sEV were able to be internalized by Müller cells. Compared to advanced glycation end-products (AGEs)-induced Müller cells, sEV coculture decreased Cullin3 neddylation, activated Nrf2 signal pathway to combat ROS-induced inflammation. The barrier function of endothelial cells was impaired when endothelial cells were treated with the supernatant of AGEs-induced Müller cells, but was restored when treated with supernatant of AGEs-induced Müller cells cocultured with sEV. The protective effect of sEV was, however, compromised when miR-143-3p was inhibited in sEV. Moreover, the protective efficacy of sEV was diminished when NEDD8 was overexpressed in Müller cells. These findings showed MSC-sEV delivered miR-143-3p to inhibit Cullin3 neddylation, stabilizing Nrf2 to counteract ROS-induced inflammation and reducing vascular leakage. Our findings suggest that MSC-sEV may be a potential nanotherapeutic agent for DR, and that Cullin3 neddylation could be a new target for DR therapy.

The Double-Edged Effects of MLN4924: Rethinking Anti-Cancer Drugs Targeting the Neddylation Pathway

(1) Background: The neddylation pathway assumes a pivotal role in the initiation and progression of cancer. MLN4924, a potent small-molecule inhibitor of the NEDD8-activating enzyme (NAE), effectively intervenes in the early stages of the neddylation pathway. By instigating diverse cellular responses, such as senescence and apoptosis in cancer cells, MLN4924 also exerts regulatory effects on non-malignant cells within the tumor microenvironment (TME) and tumor virus-infected cells, thereby impeding the onset of tumors. Consequently, MLN4924 has been widely acknowledged as a potent anti-cancer drug. (2) Recent findings: Nevertheless, recent findings have illuminated additional facets of the neddylation pathway, revealing its active involvement in various biological processes detrimental to the survival of cancer cells. This newfound understanding underscores the dual role of MLN4924 in tumor therapy, characterized by both anti-cancer and pro-cancer effects. This dichotomy is herein referred to as the "double-edged effects" of MLN4924. This paper delves into the intricate relationship between the neddylation pathway and cancer, offering a mechanistic exploration and analysis of the causes underlying the double-edged effects of MLN4924-specifically, the accumulation of pro-cancer neddylation substrates. (3) Perspectives: Here, the objective is to furnish theoretical support and novel insights that can guide the development of next-generation anti-cancer drugs targeting the neddylation pathway.

Management of Uterine Fibroids and Sarcomas: The Palermo Position Paper

BACKGROUND

Uterine fibroids are benign monoclonal tumors originating from the smooth muscle cells of the myometrium, constituting the most prevalent pathology within the female genital tract. Uterine sarcomas, although rare, still represent a diagnostic challenge and should be managed in centers with adequate expertise in gynecological oncology.

OBJECTIVES

This article is aimed to summarize and discuss cutting-edge elements about the diagnosis and management of uterine fibroids and sarcomas.

METHODS

This paper is a report of the lectures presented in an expert meeting about uterine fibroids and sarcomas held in Palermo in February 2023.

OUTCOME

Overall, the combination of novel molecular pathways may help combine biomarkers and expert ultrasound for the differential diagnosis of uterine fibroids and sarcomas. On the one hand, molecular and cellular maps of uterine fibroids and matched myometrium may enhance our understanding of tumor development compared to histologic analysis and whole tissue transcriptomics, and support the development of minimally invasive treatment strategies; on the other hand, ultrasound imaging allows in most of the cases a proper mapping the fibroids and to differentiate between benign and malignant lesions, which need appropriate management.

CONCLUSIONS AND OUTLOOK

The choice of uterine fibroid management, including pharmacological approaches, surgical treatment, or other strategies, such as high-intensity focused ultrasound (HIFU), should be carefully considered, taking into account the characteristics of the patient and reproductive prognosis.

The KEAP1-NRF2 pathway: Targets for therapy and role in cancer

The KEAP1-NRF2 pathway is the key regulator of cellular defense against both extrinsic and intrinsic oxidative and electrophilic stimuli. Since its discovery in the 1990s, its seminal role in various disease pathologies has become well appreciated, motivating research to elucidate the intricacies of NRF2 signaling and its downstream effects to identify novel targets for therapy. In this graphical review, we present an updated overview of the KEAP1-NRF2 signaling, focusing on the progress made within the past ten years. Specifically, we highlight the advances made in understanding the mechanism of activation of NRF2, resulting in novel discoveries in its therapeutic targeting. Furthermore, we will summarize new findings in the rapidly expanding field of NRF2 in cancer, with important implications for its diagnostics and treatment.

Inherited mutations affecting the SRCAP complex are central in moderate-penetrance predisposition to uterine leiomyomas

Uterine leiomyomas (ULs) are benign smooth muscle tumors that are common in premenopausal women. Somatic alterations in MED12, HMGA2, FH, genes encoding subunits of the SRCAP complex, and genes involved in Cullin 3-RING E3 ligase neddylation are mutually exclusive UL drivers. Established predisposition genes explain only partially the estimated heritability of leiomyomas. Here, we examined loss-of-function variants across 18,899 genes in a cohort of 233,614 White European women, revealing variants in four genes encoding SRCAP complex subunits (YEATS4, ZNHIT1, DMAP1, and ACTL6A) with a significant association to ULs, and YEATS4 and ZNHIT1 strikingly rank first and second, respectively. Positive mutation status was also associated with younger age at diagnosis and hysterectomy. Moderate-penetrance UL risk was largely attributed to rare non-synonymous mutations affecting the SRCAP complex. To examine this disease phenotype more closely, we set out to identify inherited mutations affecting the SRCAP complex in our in-house sample collection of Finnish individuals with ULs (n = 860). We detected one individual with an ACTL6A splice-site mutation, two individuals with a YEATS4 missense mutation, and four individuals with DMAP1 mutations: one splice-site, one nonsense, and two missense variants. These individuals had large and/or multiple ULs, were often diagnosed at an early age, and many had family history of ULs. When a somatic second hit was found, ACTL6A and DMAP1 were silenced in tumors by somatic mutation and YEATS4 by promoter hypermethylation. Decreased H2A.Z staining was observed in the tumors, providing further evidence for the pathogenic nature of the germline mutations. Our results establish inactivation of genes encoding SRCAP complex subunits as a central contributor to moderate-penetrance UL predisposition.

Pivotal Role of Ubiquitin Carboxyl-Terminal Hydrolase L1 (UCHL1) in Uterine Leiomyoma

Uterine leiomyomas are smooth-muscle tumors originating in the myometrium and are the most common pelvic tumors in women of reproductive age. Symptomatic tumors may result in abnormal uterine bleeding, bladder dysfunction, pelvic discomfort, and reproductive issues, such as infertility and miscarriage. There are currently few non-invasive treatments for leiomyoma, but there are no practical early intervention or preventive methods. In this study, human uterine leiomyoma and myometrial tissues were used to detect the protein and mRNA expression levels of UCHL1. To explore the effects of UCHL1 knockdown and inhibition in leiomyoma and myometrial cells, we determined the mRNA expressions of COL1A1 and COL3A1. Collagen gel contraction and wound-healing assays were performed on myometrial and leiomyoma cells. We found that UCHL1 expression was considerably higher in uterine leiomyomas than in the myometrium. COL1A1 and COL3A1 expression levels were downregulated after inhibition of UCHL1 in human leiomyoma cells. Furthermore, the elimination of UCHL1 significantly decreased the migration and contractility of leiomyoma cells. In conclusion, these results indicate that UCHL1 is involved in the growth of leiomyoma in humans. For the treatment of uterine leiomyoma, targeting UCHL1 activity may be a unique and possible therapeutic strategy.