NUT Carcinoma—An Underdiagnosed Malignancy

Transcriptomic profiling of a late recurrent nuclear protein in testis carcinoma of the lung 14 years after the initial operation: a case report

Background

Nuclear protein in testis (NUT) carcinoma (NC) of the lung is a rare cancer that occurs mainly in young adolescents and adults. NC is genetically characterized by NUTM1 rearrangements, which usually take the form of BRD4-NUT fusions. The prognosis for NC is dismal, and treatment with conventional chemotherapeutic regimens is ineffective.

Case Description

We herein describe the case of a 53-year-old woman with recurrent NC of the lung 14 years after surgery for nasal cavity cancer. Chest computed tomography revealed a 5.5-cm tumor in the lower lobe of the left lung. We completely resected the recurrent lung NC via thoracotomy. Immunohistochemistry (IHC) of the lung and nasal cavity cancers showed diffuse strong expression of NUT. RNA-seq of the lung NC revealed NUTM1 rearrangement, with a fusion of BRD4 exon 10 to NUTM1 exon 4. This breakpoint has never been reported before. In addition, IHC revealed elevated expression of parathyroid hormone-like hormone in the lung NC but not in the nasal cavity NC, indicating that the lung and nasal cavity NCs were metachronous multiple primary cancers.

Conclusions

We experienced a rare recurrence of lung NC 14 years after the initial surgery. The BRD4-NUT fusion consisted of a new breakpoint. Furthermore, the expression pattern of parathyroid hormone-like hormone (PTHLH) suggested that the NCs in the nasal cavity and lung may be metachronous multiple lung cancers. This extremely rare case highlighted the possibility of identifying less malignant NCs in patients with poorly differentiated tumors via fusion gene analysis and the need to develop more effective treatment strategies for this malignancy.

Nuclear protein in testis (NUT) midline carcinoma of the larynx: A rare case report of a paediatric patient and literature review

Nuclear protein in testis (NUT) carcinoma is a rare neoplasm arising mainly from midline structures. It is an aggressive type of carcinoma associated with poor survival despite the use of multiple treatment modalities. Here, we present a case of a 17-year-old paediatric patient with NUT carcinoma of larynx, which is even rarer among all reported cases. The patient underwent surgery followed by radiotherapy and systemic treatment and he died 15 months after the diagnosis. The management of this rare disease requires further investigation.

Occult Lung Cancer-Associated Autoimmune Encephalitis Presenting as Acute Psychosis

During deployment, a 52-year-old male developed acute behavioral changes. Though initially considered to have PTSD and related agitation and confusional state, his evaluation was consistent with acute encephalopathy. Magnetic resonance imaging of the brain showed T2 hyperintensities, and CSF analysis was positive for anti-N-methyl-D-aspartate receptor antibody. A nuclear protein in testis carcinoma midline carcinoma was discovered in the lung. Immunotherapy and surgical resection led to steady improvement prior to adjuvant chemotherapy. Autoimmune encephalitis due to anti-N-methyl-D-aspartate receptor antibodies is increasingly being recognized as causal of acute behavioral change.

Brd4::Nutm1 fusion gene initiates NUT carcinoma in vivo

NUT carcinoma (NC) is an aggressive cancer with no effective treatment. About 70% of NUT carcinoma is associated with chromosome translocation events that lead to the formation of a BRD4::NUTM1 fusion gene. Because the BRD4::NUTM1 gene is unequivocally cytotoxic when ectopically expressed in cell lines, questions remain on whether the fusion gene can initiate NC. Here, we report the first genetically engineered mouse model for NUT carcinoma that recapitulates the human t(15;19) chromosome translocation in mice. We demonstrated that the mouse t(2;17) syntenic chromosome translocation, forming the Brd4::Nutm1 fusion gene, could induce aggressive carcinomas in mice. The tumors present histopathological and molecular features similar to human NC, with enrichment of undifferentiated cells. Similar to the reports of human NC incidence, Brd4::Nutm1 can induce NC from a broad range of tissues with a strong phenotypical variability. The consistent induction of poorly differentiated carcinoma demonstrated a strong reprogramming activity of BRD4::NUTM1. The new mouse model provided a critical preclinical model for NC that will lead to better understanding and therapy development for NC.

Multimodal Therapy Approaches for NUT Carcinoma by Dual Combination of Oncolytic Virus Talimogene Laherparepvec with Small Molecule Inhibitors

NUT (nuclear-protein-in-testis) carcinoma (NC) is a highly aggressive tumor disease. Given that current treatment regimens offer a median survival of six months only, it is likely that this type of tumor requires an extended multimodal treatment approach to improve prognosis. In an earlier case report, we could show that an oncolytic herpes simplex virus (T-VEC) is functional in NC patients. To identify further combination partners for T-VEC, we have investigated the anti-tumoral effects of T-VEC and five different small molecule inhibitors (SMIs) alone and in combination in human NC cell lines. Dual combinations were found to result in higher rates of tumor cell reductions when compared to the respective monotherapy as demonstrated by viability assays and real-time tumor cell growth monitoring. Interestingly, we found that the combination of T-VEC with SMIs resulted in both stronger and earlier reductions in the expression of c-Myc, a main driver of NC cell proliferation, when compared to T-VEC monotherapy. These results indicate the great potential of combinatorial therapies using oncolytic viruses and SMIs to control the highly aggressive behavior of NC cancers and probably will pave the way for innovative multimodal clinical studies in the near future.

Drug repositioning in thyroid cancer: from point mutations to gene fusions

The diagnosis of thyroid cancer (TC) has increased dramatically in recent years. Papillary TC is the most frequent type and has shown a good prognosis. Conventional treatments for TC are surgery, hormonal therapy, radioactive iodine, chemotherapy, and targeted therapy. However, resistance to treatments is well documented in almost 20% of all cases. Genomic sequencing has provided valuable information to help identify variants that hinder the success of chemotherapy as well as to determine which of those represent potentially druggable targets. There is a plethora of targeted therapies for cancer, most of them directed toward point mutations; however, chromosomal rearrangements that generate fusion genes are becoming relevant in cancer but have been less explored in TC. Therefore, it is relevant to identify new potential inhibitors for genes that are recurrent in the formation of gene fusions. In this review, we focus on describing potentially druggable variants and propose both point variants and fusion genes as targets for drug repositioning in TC.

NUT carcinoma in pediatric patients: Characteristics, therapeutic regimens, and outcomes of 11 cases registered with the German Registry for Rare Pediatric Tumors (STEP)

BACKGROUND AND AIMS

Nuclear protein of the testis (NUT) carcinoma (NC) is a rare and highly aggressive tumor defined by the presence of a somatic NUTM1 rearrangement, occurring mainly in adolescents and young adults. We analyzed the clinical and biological features of German pediatric patients (≤18 years) with NC.

METHODS

This study describes the characteristics and outcome of 11 children with NC registered in the German Registry for Rare Pediatric Tumors (STEP).

RESULTS

Eleven patients with a median age of 13.2 years (range 6.6-17.8) were analyzed. Malignant misdiagnoses were made in three patients. Thoracic/mediastinal tumors were found to be the primary in six patients, head/neck in four cases; one patient had multifocal tumor with an unknown primary. All patients presented with regional lymph node involvement, eight patients (72.7%) with distant metastases. Seven patients underwent surgery, eight radiotherapy with curative intent; polychemotherapy was administered in all patients. Novel treatment strategies including immunotherapy, targeted therapies, and virotherapy were applied in three patients. Median event-free survival and overall survival were 1.5 and 6.5 months, respectively.

CONCLUSIONS

Every undifferentiated or poorly differentiated carcinoma should undergo testing for the specific rearrangement of NUTM1, in order to initiate an intense therapeutic regimen as early as possible. As in adults, only few pediatric patients with NC achieve prolonged survival. Thus, novel therapeutic strategies should be included and tested in clinical trials.

Immunodetection of NUT Protein: Implementation, Indications, and Results in a Tertiary Reference Center

The immunodetection of NUT protein is a reliable tool to identify NUT carcinoma, a rare and still underdiagnosed tumor entity. The technique was implemented in 2017 in our department, a tertiary reference center with a large recruitment in all tumor types, including head and neck and thoracic tumors. We evaluated its use over a 6-year period (2017-2022) to (a) describe the indications for the technique, (b) determine the number of NUT carcinomas detected and confirmed by Fluorescence in situ hybridization, and (c) describe briefly the characteristics of these tumors. Over the study period, 382 NUT immunodetections were performed; the annual number of requests varied from 45 to 83. All 21 pathologists of the department made at least one request (range: 1 to 94; annual mean: 18.2). 54.7% of immunodetections were performed for internal cases, 37% for cases submitted for consultation, and 8.3% for cases submitted for confirmation of a suspected diagnosis. The main indications were poorly differentiated tumors of the head and neck region (39%) and the thorax (19.6%), and difficult-to-classify soft tissue tumors (11.8%). Twelve cases of NUT carcinoma were detected by immunohistochemistry and confirmed by Fluorescence in situ hybridization. Seven were from the head and neck region (4.7% of the tumors tested), 4 from lung or mediastinum (5.3%), 1 from an unknown primary at the time of diagnosis. In conclusion, the implementation of NUT immunodetection in the daily workflow of a pathology department improves the detection of NUT carcinoma. This becomes essential with the emergence of potential targeted therapies.

Primary pulmonary nuclear protein of the testis midline carcinoma: case report and systematic review with pooled analysis

Nuclear protein of the testis (NUT) midline carcinoma (NMC) is a rare tumor, with particularly low incidence in the lungs, and a correspondingly poor prognosis. To determine the clinicopathological characteristics, outcomes, and prognostic factors of primary pulmonary NMC, a case was reported and a systematic review was performed. Twenty-nine records, including ours, involving 62 cases, were finally included. The median age at diagnosis was 29.5 years. At presentation, the most common symptoms at presentation were cough (47.50%) and chest/back pain (37.50%). In terms of diagnosis, 32.14% of NMC cases were identified through immunohistochemistry (IHC); However, a greater number of cases may be misdiagnosed initially, and ultimately, the diagnosis of NMC was confirmed through a combination of IHC and fluorescence in situ hybridization (FISH). Despite the clinical application of various chemotherapy-based treatments, the actual effectiveness remains unsatisfactory. Furthermore, Cox regression analysis of multiple factors identified male gender and concurrent presence of pleural effusion as indicators of shorter survival time in patients. These results emphasize the importance of increased diagnostic awareness among clinical and pathology practitioners concerning NMC. While there is currently no established standard for treating NMC, a treatment approach combining multiple methods shows promise for future research. Concurrently, clinical and foundational investigations addressing variables such as gender and the presence of pleural effusion may yield valuable insights into the diagnosis and treatment of NMC.

Clinical Network Systems Biology: Traversing the Cancer Multiverse

In recent decades, cancer biology and medicine have ushered in a new age of precision medicine through high-throughput approaches that led to the development of novel targeted therapies and immunotherapies for different cancers. The availability of multifaceted high-throughput omics data has revealed that cancer, beyond its genomic heterogeneity, is a complex system of microenvironments, sub-clonal tumor populations, and a variety of other cell types that impinge on the genetic and non-genetic mechanisms underlying the disease. Thus, a systems approach to cancer biology has become instrumental in identifying the key components of tumor initiation, progression, and the eventual emergence of drug resistance. Through the union of clinical medicine and basic sciences, there has been a revolution in the development and approval of cancer therapeutic drug options including tyrosine kinase inhibitors, antibody-drug conjugates, and immunotherapy. This 'Team Medicine' approach within the cancer systems biology framework can be further improved upon through the development of high-throughput clinical trial models that utilize machine learning models, rapid sample processing to grow patient tumor cell cultures, test multiple therapeutic options and assign appropriate therapy to individual patients quickly and efficiently. The integration of systems biology into the clinical network would allow for rapid advances in personalized medicine that are often hindered by a lack of drug development and drug testing.

BET Bromodomain Inhibitors: Novel Design Strategies and Therapeutic Applications

The mammalian bromodomain and extra-terminal domain (BET) family of proteins consists of four conserved members (Brd2, Brd3, Brd4, and Brdt) that regulate numerous cancer-related and immunity-associated genes. They are epigenetic readers of histone acetylation with broad specificity. BET proteins are linked to cancer progression due to their interaction with numerous cellular proteins including chromatin-modifying factors, transcription factors, and histone modification enzymes. The spectacular growth in the clinical development of small-molecule BET inhibitors underscores the interest and importance of this protein family as an anticancer target. Current approaches targeting BET proteins for cancer therapy rely on acetylation mimics to block the bromodomains from binding chromatin. However, bromodomain-targeted agents are suffering from dose-limiting toxicities because of their effects on other bromodomain-containing proteins. In this review, we provided an updated summary about the evolution of small-molecule BET inhibitors. The design of bivalent BET inhibitors, kinase and BET dual inhibitors, BET protein proteolysis-targeting chimeras (PROTACs), and Brd4-selective inhibitors are discussed. The novel strategy of targeting the unique C-terminal extra-terminal (ET) domain of BET proteins and its therapeutic significance will also be highlighted. Apart from single agent treatment alone, BET inhibitors have also been combined with other chemotherapeutic modalities for cancer treatment demonstrating favorable clinical outcomes. The investigation of specific biomarkers for predicting the efficacy and resistance of BET inhibitors is needed to fully realize their therapeutic potential in the clinical setting.

Synthesis, Biochemical Characterization, and Genetic Encoding of a 1,2,4-Triazole Amino Acid as an Acetyllysine Mimic for Bromodomains of the BET Family

Lysine acetylation is a charge-neutralizing post-translational modification of proteins bound by bromodomains (Brds). A 1,2,4-triazole amino acid (ApmTri) was established as acetyllysine (Kac) mimic recruiting Brds of the BET family in contrast to glutamine commonly used for simulating this modification. Optimization of triazole substituents and side chain spacing allowed BET Brd recruitment to ApmTri-containing peptides with affinities similar to native substrates. Crystal structures of ApmTri-containing peptides in complex with two BET Brds revealed the binding mode which mirrored that of Kac ligands. ApmTri was genetically encoded and recombinant ApmTri-containing proteins co-enriched BRD3(2) from cellular lysates. This interaction was blocked by BET inhibitor JQ1. With genetically encoded ApmTri, biochemistry is now provided with a stable Kac mimic reflecting charge neutralization and Brd recruitment, allowing new investigations into BET proteins in vitro and in vivo.