Adipogenesis associated Mth938 domain containing (AAMDC) represents an uncharacterized oncogene amplified in aggressive estrogen receptor-positive breast cancers. We uncover that AAMDC regulates the ...expression of several metabolic enzymes involved in the one-carbon folate and methionine cycles, and lipid metabolism. We show that AAMDC controls PI3K-AKT-mTOR signaling, regulating the translation of ATF4 and MYC and modulating the transcriptional activity of AAMDC-dependent promoters. High AAMDC expression is associated with sensitization to dactolisib and everolimus, and these PI3K-mTOR inhibitors exhibit synergistic interactions with anti-estrogens in IntClust2 models. Ectopic AAMDC expression is sufficient to activate AKT signaling, resulting in estrogen-independent tumor growth. Thus, AAMDC-overexpressing tumors may be sensitive to PI3K-mTORC1 blockers in combination with anti-estrogens. Lastly, we provide evidence that AAMDC can interact with the RabGTPase-activating protein RabGAP1L, and that AAMDC, RabGAP1L, and Rab7a colocalize in endolysosomes. The discovery of the RabGAP1L-AAMDC assembly platform provides insights for the design of selective blockers to target malignancies having the AAMDC amplification.
Brain metastases are devastating complications of cancer. The blood-brain barrier (BBB), which protects the normal brain, morphs into an inadequately characterized blood-tumor barrier (BTB) when ...brain metastases form, and is surrounded by a neuroinflammatory response. These structures contribute to poor therapeutic efficacy by limiting drug uptake. Here, we report that experimental breast cancer brain metastases of low- and high permeability to a dextran dye exhibit distinct microenvironmental gene expression patterns. Astrocytic sphingosine-1 phosphate receptor 3 (S1P3) is upregulated in the neuroinflammatory response of the highly permeable lesions, and is expressed in patients' brain metastases. S1P3 inhibition functionally tightens the BTB in vitro and in vivo. S1P3 mediates its effects on BTB permeability through astrocytic secretion of IL-6 and CCL2, which relaxes endothelial cell adhesion. Tumor cell overexpression of S1P3 mimics this pathway, enhancing IL-6 and CCL-2 production and elevating BTB permeability. In conclusion, neuroinflammatory astrocytic S1P3 modulates BTB permeability.
ALK alterations in salivary gland carcinomas Majewska, Hanna; Gorczyński, Adam; Czapiewski, Piotr ...
Virchows Archiv : an international journal of pathology,
05/2021, Letnik:
478, Številka:
5
Journal Article
Recenzirano
Odprti dostop
Salivary gland carcinomas represent a heterogeneous group of poorly characterized head and neck tumors. The purpose of this study was to evaluate
ALK
gene and protein aberrations in a large, ...well-characterized cohort of these tumors. A total of 182 salivary gland carcinomas were tested for anaplastic lymphoma kinase (ALK) positivity by immunohistochemistry (IHC) using the cut-off of 10% positive cells. ALK positive tumors were subjected to FISH analysis and followed by hybrid capture–based next generation sequencing (NGS). Of the 182 tumors, 8 were ALK positive by IHC. Further analysis using hybrid capture NGS analysis revealed a novel
MYO18A
(Exon1-40)-
ALK
(exon 20-29) gene fusion in one case of intraductal carcinoma. Additional genomic analyses resulted in the detection of inactivating mutations in
BRAF
and
TP53
, as well as amplifications of
ERBB2
and
ALK
.
ALK
rearrangements are a rare entity in salivary gland carcinomas. We identified a potentially targetable novel
ALK
fusion in an intraductal carcinoma of minor salivary glands.
One of the most common subgroups of cutaneous T-cell lymphomas is that of primary cutaneous CD30-positive lymphoproliferative disorders. The group includes lymphomatoid papulosis (LyP) and primary ...cutaneous anaplastic large cell lymphoma (pcALCL), as well as some borderline cases. Recently, significant progress has been made in understanding the genetics and treatment of these disorders. This review article summarises the clinical evidence supporting the current treatment options for these diseases. Recent years have seen the introduction of novel agents into clinical practice; most of these target CD30, such as anti-CD30 monoclonal antibodies and conjugated antibodies (brentuximab vedotin), bispecific antibodies and cellular therapies, particularly anti-CD30 CAR-T cells. This paper briefly reviews the biology of CD30 that makes it a good therapeutic target and describes the anti-CD30 therapies that have emerged to date.
Diffuse malignant mesothelioma of the pleura is a highly aggressive tumor typically associated with short survival. ALCAM (CD166), a type I transmembrane protein, is a member of the immunoglobulin ...superfamily. In normal cells, ALCAM regulates physiological processes such as angiogenesis and immune response. In cancer, it is associated with neoplastic progression, including invasion, migration, and metastasis. Furthermore, ALCAM is considered one of the cancer stem cell markers such as ALDH1 (ALDH1A1) and SALL4. The PD-L1 (CD274)/PD-1 (PDCD1, CD279) pathway is crucial for the modulation of immune responses in normal cells. Nevertheless, pathologic activation of the PD-L1/PD-1 pathway participates in immune evasion by tumor cells. Many PD-L1–expressing tumor cells have been identified in different types of cancer, including malignant mesothelioma. In this study, 175 well-characterized primary diffuse pleural mesotheliomas, including the epithelioid (n = 148), biphasic (n = 15), and sarcomatoid (n = 12) histotypes, were evaluated immunohistochemically for cancer stem cell markers (ALCAM, ALDH1, and SALL4) and PD-L1 expression. Twenty-five percent of the mesotheliomas (43/175) expressed ALCAM, whereas ALDH1 and SALL4 positivity was seen in 1% to 2% of cases. Thirty-three percent of the analyzed tumors (57/175) contained PD-L1–positive cells. Overall survival was significantly decreased in the cohort of patients with ALCAM- or PD-L1–positive tumors (both P < .01). Furthermore, the multivariate Cox hazards regression analysis identified ALCAM and PD-L1 (both P < 0.01) as potential independent risk factors. Thus, a combination of these 2 markers might be useful for prognostication and planning the treatment of patients with malignant pleural mesothelioma.
•PD-L1 and stem cell marker expressions were analyzed in malignant mesotheliomas.•PD-L1 and ALCAM were expressed in 33% and 25% of mesothelioma cases, respectively.•The Cox proportional hazards model identified these proteins as independent risk factors for death.
Warthin tumour is the second most common benign neoplasm of salivary glands. Despite its relatively characteristic histology, it may sometimes mimic other lesions. Here, we report two female ...non-smoker patients diagnosed with low-grade mucoepidermoid carcinoma with oncocytic epithelium and prominent lymphoid (Warthin-like) stroma and with molecularly confirmed
MAML2
rearrangement. In addition, we screened a consecutive series of 114 Warthin tumour cases by means of
MAML2
break apart fluorescence in situ hybridization to assess its value in differential diagnosis.
MAML2
rearrangement was detected in both mucoepidermoid carcinoma cases, while all Warthin tumours were negative. Taking into account the literature data, Warthin-like mucoepidermoid carcinomas are more frequently observed in women, while a slight male predominance and smoking history are typical for Warthin tumour. In addition, the patients with Warthin-like mucoepidermoid carcinoma were significantly younger than those with Warthin tumour. To conclude, Warthin-like mucoepidermoid carcinoma may usually be suspected based on histology, while the diagnosis can be confirmed by means of molecular assays such as FISH. The investigation of
MAML2
status is particularly advised when Warthin tumour is considered in a young, non-smoking, female patient.
Melanomas are known for their diverse morphological features, presenting a diagnostic challenge for pathologists. Uncommon variations of melanoma can exhibit distinct cytological and ...histomorphological characteristics, including ganglioneuroblastic differentiation. However, this phenomenon is extremely rare, with only a few documented cases. Here, we present a unique case of an occult metastatic melanoma with ganglioneuroblastic differentiation developing in a 76-year-old male. The diagnosis was based on histopathology, immunophenotyping, and molecular testing, which revealed SOX10 positivity and an NRAS mutation. Notably, classic melanoma markers HMB45 and melan-A were negative, highlighting the importance of considering alternative markers. This case emphasizes the significance of immunohistochemistry and molecular investigation in diagnosing melanomas with unusual features and identifying appropriate candidates for immune checkpoint therapy. Additionally, the occurrence of ganglioneuroblastic differentiation further supports a shared histogenetic origin from the neural crest. Improved understanding of such rare variants contributes to accurate diagnosis and optimal management of melanoma patients.
Brain metastases (BMs) in ovarian cancer (OC) are a rare event. BMs occur most frequently in high-grade serous (HGS) OC. The molecular features of BMs in HGSOC are poorly understood. We performed a ...whole-exome sequencing analysis of ten matched pairs of formalin-fixed paraffin-embedded samples from primary HGSOC and corresponding BMs. Enrichment significance (p value; false discovery rate) was computed using the Reactome, the Kyoto Encyclopedia of Genes and Genomes pathway collections, and the Gene Ontology Biological Processes. Germline DNA damage repair variants were found in seven cases (70%) and involved the BRCA1, BRCA2, ATM, RAD50, ERCC4, RPA1, MLHI, and ATR genes. Somatic mutations of TP53 were found in nine cases (90%) and were the only stable mutations between the primary tumor and BMs. Disturbed pathways in BMs versus primary HGSOC constituted a complex network and included the cell cycle, the degradation of the extracellular matrix, cell junction organization, nucleotide metabolism, lipid metabolism, the immune system, G-protein-coupled receptors, intracellular vesicular transport, and reaction to chemical stimuli (Golgi vesicle transport and olfactory signaling). Pathway analysis approaches allow for a more intuitive interpretation of the data as compared to considering single-gene aberrations and provide an opportunity to identify clinically informative alterations in HGSOC BM.
We investigated the status of estrogen receptor alpha (ERα), progesterone receptor (PR), and epidermal growth factor receptor 2 (HER2) in primary tumor and in the corresponding brain metastases in a ...consecutive series of breast cancer patients. Additionally, we studied factors potentially influencing conversion and evaluated its association with survival.
The study group included 120 breast cancer patients. ERα, PR, and HER2 status in primary tumors and in matched brain metastases was determined centrally by immunohistochemistry and/or fluorescence in situ hybridization.
Using the Allred score of ≥ 3 as a threshold, conversion of ERα and PR in brain metastases occurred in 29% of cases for both receptors, mostly from positive to negative. Conversion of HER2 occurred in 14% of patients and was more balanced either way. Time to brain relapse and the use of chemotherapy or trastuzumab did not influence conversion, whereas endocrine therapy induced conversion of ERα (P = 0.021) and PR (P = 0.001), mainly towards their loss. Receptor conversion had no significant impact on survival.
Receptor conversion, particularly loss of hormone receptors, is a common event in brain metastases from breast cancer, and endocrine therapy may increase its incidence. Receptor conversion does not significantly affect survival.
The etiology of sarcoidosis is unknown, but microbial agents are suspected as triggers.
We sought to identify bacterial, fungal, or viral lineages in specimens from patients with sarcoidosis enriched ...relative to control subjects using metagenomic DNA sequencing. Because DNA from environmental contamination contributes disproportionately to samples with low authentic microbial content, we developed improved methods for filtering environmental contamination.
We analyzed specimens from subjects with sarcoidosis (n = 93), control subjects without sarcoidosis (n = 72), and various environmental controls (n = 150). Sarcoidosis specimens consisted of two independent sets of formalin-fixed, paraffin-embedded lymph node biopsies, BAL, Kveim reagent, and fresh granulomatous spleen from a patient with sarcoidosis. All specimens were analyzed by bacterial 16S and fungal internal transcribed spacer ribosomal RNA gene sequencing. In addition, BAL was analyzed by shotgun sequencing of fractions enriched for viral particles, and Kveim and spleen were subjected to whole-genome shotgun sequencing.
In one tissue set, fungi in the Cladosporiaceae family were enriched in sarcoidosis compared with nonsarcoidosis tissues; in the other tissue set, we detected enrichment of several bacterial lineages in sarcoidosis but not Cladosporiaceae. BAL showed limited enrichment of Aspergillus fungi. Several microbial lineages were detected in Kveim and spleen, including Cladosporium. No microbial lineage was enriched in more than one sample type after correction for multiple comparisons.
Metagenomic sequencing revealed enrichment of microbes in single types of sarcoidosis samples but limited concordance across sample types. Statistical analysis accounting for environmental contamination was essential to avoiding false positives.
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