Genomic profile analysis of leiomyomas with bizarre nuclei and fumarate hydratase deficient leiomyomas: Strengths, weaknesses, and limitations of array-CGH interpretation.

A close relationship has been demonstrated between genomic complexity and clinical outcome in uterine smooth muscle tumors. We studied the genomic profiles by array-CGH of 28 fumarate hydratase deficient leiomyomas and 37 leiomyomas with bizarre nuclei (LMBN) from 64 patients. Follow-up was available for 46 patients (from three to 249 months, mean 87.3 months). All patients were alive without evidence of disease. For 51 array-CGH interpretable tumors the mean Genomic Index (GI) was 16.4 (median: 9.8; from 1 to 57.8), significantly lower than the mean GI in LMS (mean GI 51.8, p < 0.001). We described three groups: (1) a group with FH deletion (24/58) with low GI (mean GI: 11 vs. 22,4, p = 0.02), (2) a group with TP53 deletion (17/58) with higher GI (22.4 vs. 11 p = 0.02), and (3) a group without genomic events on FH or TP53 genes (17/58) (mean GI:18.3; from 1 to 57.8). Because none of these tumors recurred and none showed morphological features of LMS we concluded that GI at the cut-off of 10 was not applicable in these subtypes of LM. By integration of all those findings, a GI <10 in LMBN remains a valuable argument for benignity. Conversely, in LMBN a GI >10 or alteration in tumor suppressor genes, should not alone warrant a diagnosis of malignancy. Nine tumors were tested with Nanocind CINSARC® signature and all were classified in low risk of recurrence. We propose, based on our observations, a diagnostic approach of these challenging lesions.

SMARCB1 (INI1) Deficient Tumours of the Uterine Cervix: Report of Two Cases, Including One Associated With an NTRK Fusion.

Pathogenic variants (mutations) and other molecular events involving subunits of the SWItch/Sucrose Non-Fermentable chromatin remodelling complex are common in a wide variety of malignancies. Many of these neoplasms are characterized by undifferentiated morphology. They arise at a variety of sites in the female genital tract but have rarely been reported in the uterine cervix. We report 2 primary cervical neoplasms arising in young women (ages 28 and 29 yr) exhibiting loss of nuclear immunoreactivity with SMARCB1 (INI1). In one case, which had a mixture of epithelioid and spindle cells, molecular studies revealed no SMARCB1 pathogenic variant, but showed a SPECCL1::NTRK 3 fusion, in keeping with an NTRK fusion sarcoma. The second case exhibited rhabdoid morphology and molecular testing confirmed a SMARCB1 pathogenic variant (c.425 T>G:p.(Leu142Ter) which, interpreted in conjunction with the morphology and immunohistochemistry, resulted in classification as a proximal-type epithelioid sarcoma. To our knowledge, this is the first reported cervical neoplasm exhibiting a SMARCB1 pathogenic variant and the first NTRK fusion sarcoma showing SMARCB1 protein loss. We discuss the diagnostic challenges and complexities of the molecular findings.

Pan-TRK immunohistochemistry in gynaecological mesenchymal tumours: diagnostic implications and pitfalls.

AIMS: NTRK-rearranged sarcomas of the female genital tract mainly occur in the uterus (more commonly cervix than corpus) and are characterized by a "fibrosarcoma-like" morphology and NTRK gene rearrangements. These neoplasms may exhibit histological overlap with other entities and can present diagnostic difficulties without molecular confirmation. Pan-TRK immunohistochemistry was developed to identify tumours harbouring NTRK rearrangements. The aim of this study was to characterize pan-TRK immunohistochemical expression in a large cohort of gynaecological mesenchymal neoplasms and investigate the utility of pan-TRK immunohistochemistry to distinguish NTRK-rearranged sarcoma from its mimics. METHODS AND RESULTS: A total of 473 gynaecological mesenchymal tumours (461 without known NTRK fusions and 12 NTRK-rearranged sarcomas) were selected. Pan-TRK immunohistochemistry (EPR17341, Abcam) was performed on whole tissue sections and tissue microarrays. Molecular interrogation of pan-TRK positive tumours was performed by RNA sequencing or fluorescence in situ hybridization (FISH). Of the 12 NTRK-rearranged sarcomas, 11 (92%) exhibited diffuse (≥70%) cytoplasmic pan-TRK staining with moderate/marked intensity, while the other was negative. Eleven (2.4%) additional tumours also exhibited pan-TRK immunohistochemical expression: three low-grade endometrial stromal sarcomas, seven high-grade endometrial stromal sarcomas, and an undifferentiated uterine sarcoma. Molecular confirmation of the absence of NTRK rearrangements was possible in nine of these tumours. Of these nine neoplasms, seven exhibited focal/multifocal (<70%) pan-TRK cytoplasmic staining with weak/moderate intensity. CONCLUSION: Even though pan-TRK immunohistochemical expression is not entirely sensitive or specific for NTRK-rearranged sarcomas, these neoplasms tend to exhibit diffuse staining of moderate/strong intensity, unlike its mimics. Pan-TRK should be performed in monomorphic uterine (corpus and cervix) spindle cell neoplasms that are negative for smooth muscle markers and hormone receptors and positive for CD34 and/ or S100. Ultimately, the diagnosis requires molecular confirmation.

Development of Radiopharmaceuticals for NPY Receptor-5 (Y5) Nuclear Imaging in Tumors by Synthesis of Specific Agonists and Investigation of Their Binding Mode.

The neuropeptide-Y (NPY) family acts through four G protein-coupled receptor subtypes in humans, namely, Y1, Y2, Y4, and Y5. A growing body of evidence suggest the involvement of the NPY system in several cancers, notably the Y5 subtype, thus acting as a relevant target for the development of radiopharmaceuticals for imaging or targeted radionuclide therapy (TRT). Here, the [cPP(1-7),NPY(19-23),Ala31,Aib32,Gln34]hPP scaffold, further referred to as sY5ago, was modified with a DOTA chelator and radiolabeled with 68Ga and 111In and investigated in vitro and in vivo using the MCF-7 model. For in vivo studies, MCF-7 cells were orthotopically implanted in female nude mice and imaging with small animal positron emission tomography/computed tomography (µPET/CT) was performed. At the end of imaging, the mice were sacrificed. A scrambled version of sY5ago, which was also modified with a DOTA chelator, served as a negative control (DOTA-[Nle]sY5ago_scrambled). sY5ago and DOTA-sY5ago showed subnanomolar affinity toward the Y5 (0.9 ± 0.1 and 0.8 ± 0.1 nM, respectively) and a single binding site at the Y5 was identified. [68Ga]Ga-DOTA-sY5ago and [111In]In-DOTA-sY5ago were hydrophilic and showed high specific internalization (1.61 ± 0.75%/106 cells at 1 h) and moderate efflux (55% of total binding externalized at 45 min). On µPET/CT images, most of the signal was depicted in the kidneys and the liver. MCF-7 tumors were clearly visualized. On biodistribution studies, [68Ga]Ga-DOTA-sY5ago was eliminated by the kidneys (∼60 %ID/g). The kidney uptake is Y5-mediated. A specific uptake was also noted in the liver (5.09 ± 1.15 %ID/g vs 1.13 ± 0.21 %ID/g for [68Ga]Ga-DOTA-[Nle]sY5ago_scrambled, p < 0.05), the lungs (1.03 ± 0.34 %ID/g vs 0.20 %ID/g, p < 0.05), and the spleen (0.85 ± 0.09%ID/g vs 0.16 ± 0.16%ID/g, p < 0.05). In MCF-7 tumors, [68Ga]Ga-DOTA-sY5ago showed 12-fold higher uptake than [68Ga]Ga-DOTA-[Nle]sY5ago_scrambled (3.43 ± 2.32 vs 0.27 ± 0.15 %ID/g, respectively, p = 0.0008) at 1 h post-injection. Finally, a proof-of-principle tissular micro-imaging study on a human primary cancer sample showed weak binding of [111In]In-DOTA-sY5ago in prostatic intra-neoplasia and high binding in the ISUP1 lesion while normal prostate was free of signal.

PRAME immunohistochemistry in soft tissue tumors and mimics: a study of 350 cases highlighting its imperfect specificity but potentially useful diagnostic applications.

Preferentially expressed antigen in melanoma (PRAME) immunohistochemistry is currently used in pathology for the assessment of melanocytic neoplasms; however, knowledge of its expression patterns in soft tissue tumors is limited. PRAME immunohistochemistry (clone QR005) was assessed on whole tissue sections of 350 soft-tissue tumors and mimics (> 50 histotypes). PRAME immunoreactivity was evaluated as follows: 0 "negative" (0% positive cells); 1+ (1-25% positive cells); 2+ (26-50% positive cells); 3+ (51-75% positive cells), and 4+ "diffuse" (> 75% positive cells). PRAME was expressed in 111 lesions (0 benign, 6 intermediate malignancy, and 105 malignant), including fibrosarcomatous dermatofibrosarcoma protuberans (2/4, 0 diffuse), NTRK-rearranged spindle cell neoplasm (2/4, 0 diffuse), atypical fibroxanthoma (1/7, 0 diffuse), Kaposi sarcoma (1/5, 0 diffuse), myxoid liposarcoma (11/11, 9 diffuse), synovial sarcoma (11/11, 6 diffuse), intimal sarcoma (7/7, 5 diffuse), biphenotypic sinonasal sarcoma (3/3, 1 diffuse), angiosarcoma (10/15, 6 diffuse), malignant peripheral nerve sheath tumor (9/12, 4 diffuse), pleomorphic rhabdomyosarcoma (2/3, 2 diffuse), alveolar rhabdomyosarcoma (2/6, 0 diffuse), embryonal rhabdomyosarcoma (7/7, 4 diffuse), undifferentiated pleomorphic sarcoma (2/12, 1 diffuse), leiomyosarcoma (2/15, 1 diffuse), clear cell sarcoma of soft tissue (1/10, 0 diffuse), low-grade fibromyxoid sarcoma (1/5, 0 diffuse), Ewing sarcoma (2/10, 1 diffuse), CIC-rearranged sarcoma (8/8, 4 diffuse), BCOR-sarcoma (2/5, 1 diffuse), melanoma (20/20, 14 diffuse), and thoracic SMARCA4-deficient undifferentiated tumor (5/5, all diffuse). All tested cases of spindle cell lipoma, dedifferentiated/pleomorphic liposarcoma, dermatofibrosarcoma protuberans, solitary fibrous tumor, inflammatory myofibroblastic tumor, myxoinflammatory fibroblastic sarcoma, nodular fasciitis, myxofibrosarcoma, epithelioid hemangioendothelioma, atypical vascular lesion, hemangioma, lymphangioma, vascular malformation, papillary endothelial hyperplasia, GIST, gastrointestinal clear-cell sarcoma, malignant melanotic nerve sheath tumor, neurofibroma, schwannoma, granular cell tumor, alveolar soft part sarcoma, epithelioid sarcoma, extraskeletal myxoid chondrosarcoma, myoepithelioma, ossifying fibromyxoid tumor, angiomatoid fibrous histiocytoma, PEComa, dermatofibroma, pleomorphic dermal sarcoma, and chordoma were negative. PRAME shows imperfect specificity in soft-tissue pathology but may serve as a diagnostic adjunct in selected differential diagnoses that show contrasting expression patterns.

Giant Cell Tumors With HMGA2::NCOR2 Fusion : Clinicopathologic, Molecular, and Epigenetic Study of a Distinct Entity.

Giant cell tumors (GCTs) with high mobility group AT-Hook 2 ( HMGA2 )::nuclear receptor corepressor 2 ( NCOR2 ) fusion are rare mesenchymal tumors of controversial nosology, which have been anecdotally reported to respond to CSFR1 inhibitors. Here, we performed a comprehensive study of 6 GCTs with HMGA2::NCOR2 fusion and explored their relationship with other giant cell-rich neoplasms. Tumors occurred in 4 females and 2 males ranging in age from 17 to 32 years old (median 24). Three lesions originated in subcutaneous soft tissue and 3 in bone. Tumor size ranged from 20 to 33 mm (median 27 mm). The lesions had a nodular/multinodular architecture and were composed of sheets of mononuclear "histiocytoid" cells with uniform nuclei intermingled with multinucleated giant cells. Mitotic activity was low and nuclear atypia and metaplastic bone were absent. Variable findings included necrosis, cystic degeneration, lymphocytic infiltrate (sometimes forming nodules), and xanthogranulomatous inflammation. On immunohistochemistry, all cases focally expressed pan-keratin and were negative with SATB2 and H3.3G34W. Whole RNA-sequencing was performed in all cases of GCT with HMGA2::NCOR2 fusion and a subset of giant cell-rich tumors (tenosynovial-GCT, n = 19 and "wild-type" GCT of soft tissue, n = 9). Hierarchical clustering of RNA-sequencing data showed that GCT with HMGA2::NCOR2 fusion formed a single cluster, independent of the other 2 entities. Methylome profiling showed similar results, but the distinction from "wild-type" GCT of soft tissue was less flagrant. Gene expression analysis showed similar levels of expression of the CSF1/CSFR1 axis between GCT with HMGA2::NCOR2 fusion and tenosynovial-GCT, supporting their potential sensitivity to CSFR1 inhibitors. Clinical follow-up was available for 5 patients (range: 10 to 64 mo; median 32 mo). Three patients (60%) experienced local recurrences, whereas none had distant metastases or died of disease. Overall, our study confirms and expands previous knowledge on GCT with HMGA2::NCOR2 fusion and supports its inclusion as an independent entity.

Standardized Pathology Screening of Mature Tertiary Lymphoid Structures in Cancers.

Mature tertiary lymphoid structures (mTLSs) are organized lymphoid structures containing B lymphocytes admixed to CD23+ follicular dendritic cells. Their presence has been linked to improved survival and sensitivity to immune checkpoint inhibitors in several cancers, emerging as a promising pancancer biomarker. However, the requirements for any biomarker are clear methodology, proven feasibility, and reliability. In 357 patients' samples, we studied tertiary lymphoid structures (TLSs) parameters using multiplex immunofluorescence (mIF), hematoxylin-eosin-saffron (HES) staining, double CD20/CD23 staining, and single CD23 immunohistochemistry. The cohort included carcinomas (n = 211) and sarcomas (n = 146), gathering biopsies (n = 170), and surgical specimens (n = 187). mTLSs were defined as TLSs containing either a visible germinal center on HES staining or CD23+ follicular dendritic cells. Focusing on 40 TLSs assessed using mIF, double CD20/CD23 staining was less sensitive than mIF to assess maturity in 27.5% (n = 11/40) but was rescued by single CD23 staining in 90.9% (n = 10/11). In 97 patients, several samples (n = 240) were reviewed to characterize TLS distribution. The likelihood of finding TLSs in surgical material was 6.1 higher than in biopsy and 2.0 higher in primary samples than in metastasis after adjustment with a type of sample. Interrater agreement rates over 4 examiners were 0.65 (Fleiss kappa, 95% CI [0.46, 0.90]) for the presence of TLS and 0.90 for maturity (95% CI [0.83, 0.99]). In this study, we propose a standardized method to screen mTLSs in cancer samples using HES staining and immunohistochemistry that can be applied to all specimens.

Recurrent YAP1::MAML2 fusions in "nodular necrotizing" variants of myxoinflammatory fibroblastic sarcoma: a comprehensive study of 7 cases.

Myxoinflammatory fibroblastic sarcoma (MIFS) is a rare soft tissue tumor with a predilection for the distal extremities and a tendency for local recurrence. Morphologically, MIFS consists of spindle and bizarre epithelioid cells resembling virocytes embedded in a fibrous to myxoid stroma with an abundant inflammatory infiltrate. Importantly, the molecular landscape of MIFS is wide and includes: VGLL3 amplification, BRAF fusion/amplification and OGA/TGFBR3 rearrangements. In this study, we describe a variant of MIFS showing a frequent nodular configuration associated with necrosis and recurrent YAP1::MAML2 fusions. The cohort consisted of 7 patients (4 females and 3 males) ranging in age from 21 to 71 years (median: 47 years). Two tumors (28%) occurred in acral locations while the remaining cases were more widely distributed (thigh, n = 2; arm, n = 1; neck; n = 1; chest-wall, n = 1). Tumor size ranged from 10 to 38 mm (median: 20 mm). Histologically, lesions frequently presented as nodules with central areas of necrosis, and were predominantly composed of sheets of epithelioid cells with large vesicular nuclei and prominent nucleoli (Reed-Sternberg-like cells or virocytes). The stroma was mostly fibrous and showed a polymorphous inflammatory infiltrate. Myxoid stromal changes were focally seen in one case, and pseudolipoblasts were absent. The immunophenotype was nonspecific, with only pan-keratin (AE1-AE3) and cyclin D1 expression in a subset of cases. RNA-Sequencing detected YAP1::MAML2 fusions in 3/7 cases; aCGH showed no significant gene copy number variations in 4 tested cases, and FISH analysis showed no VGLL3 amplification in 1 tested case. Follow-up was available for 6 cases, ranging from 7 to 63 months (median: 42 months). Local recurrence and metastasis were not seen and one tumor showed spontaneous regression following initial biopsy. In conclusion, we describe a novel variant of MIFS with distinctive clinicopathological and molecular features for which we propose the term "nodular necrotizing" MIFS.

Biomarkers Associated with Lymph Nodal Metastasis in Endometrioid Endometrial Carcinoma.

INTRODUCTION: Lymph node metastasis is determinant in the prognosis and treatment of endometrioid endometrial cancer (EEC) but the risk-benefit balance of surgical lymph node staging remains controversial. OBJECTIVE: Describe the pathways associated with lymph node metastases in EEC detected by whole RNA sequencing. METHODS: RNA-sequencing was performed on a retrospective series of 30 non-metastatic EEC. N+ and N- patients were matched for tumoral size, tumoral grade and myometrial invasion. RESULTS: Twenty-eight EECs were analyzable (16 N+ and 12 N-). Bioinformatics Unsupervised analysis revealed three patterns of expression, enriched in N+, mix of N+/N- and enriched in N-, respectively. The cluster with only N+ patient overexpressed extra cellular matrix, epithelial to mesenchymal and smooth muscle contraction pathways with respect to the N- profile. Differential expression analysis between N+ and N- was used to generate a 54-genes signature with an 87% accuracy. CONCLUSION: RNA-expression analysis provides a basis to develop a gene expression-based signature that could pre-operatively predict lymph node invasion.

PTEN alterations in sporadic and BRCA1-associated triple negative breast carcinomas.

The similarities between sporadic basal-like breast cancer (BLBC) and BRCA1-mutated breast tumours raise the possibility that deregulation of the same pathway may underlie these tumour types. The aim of this study was to determine if PTEN aberrations are characteristic of both BRCA1 tumours and sporadic TN breast carcinomas with low BRCA1 expression, and can thus be used to identify sporadic tumours potentially sensitive to PARP inhibitors. Twelve BRCA1 tumours, 19 non-BRCA familial breast tumours and 71 unselected TN breast carcinomas were screened for PTEN mutations and assessed for PTEN expression and BRCA1 mRNA expression. Loss of PTEN expression was observed in 67% of BRCA1 tumours and more specifically in 89% of TN BRCA1 tumours highlighting the link between PTEN loss and BLBC in the context of germline BRCA1 mutations. Regarding unselected TN tumours, 56% showed PTEN expression loss and 35% displayed low BRCA1 mRNA expression. Unlike familial breast cancers with low BRCA1 mRNA expression, no significant correlation was observed between the loss of PTEN expression and low BRCA1 mRNA expression in this unselected TN tumours panel. Our data suggest that, unlike the germinal context, PTEN and BRCA1 alterations in sporadic TN breast tumours are independent events.

Breast hamartoma: reassessment of an under-recognised breast lesion.

AIMS: Breast hamartomas are an under-recognised lesion because they lack a distinctive microscopic appearance. Microscopic diagnosis can often conclude 'no significant lesion' or 'normal breast tissue', leading to repeated biopsies and diagnostic delay. We describe the histological, immunohistochemical and radiological features of breast hamartomas with the aim of identifying specific signs to facilitate their diagnosis and to differentiate them from normal breast and fibroepithelial lesions. METHODS AND RESULTS: Forty-seven breast hamartomas were reassessed (histological diagnosis and imaging features). An immunohistochemical study [oestrogen receptor (ER), progesterone receptor (PR), CD34, high-mobility group A2 (HMGA2)] was performed. On breast imaging, hamartomas most often presented as probably benign solid masses with circumscribed margins and variable densities. Histologically, breast hamartomas resembled normal breast, although their stromal component was predominant, separating randomly scattered epithelial elements with areas of pure collagenous stroma. Pseudoangiomatous stromal hyperplasia (PASH) was present in 93.6% of cases and CD34 antibody highlighted intralobular, perilobular and interlobular distribution of CD34-positive fibroblasts. By comparison, CD34 was mainly expressed in the intralobular normal breast tissue stroma. Hamartoma stromal cells expressed HMGA2, ER and PR in 79%, 66% and 76.3% of our cases, respectively, compared to 7.7%, 23% and 19% in normal breast tissue, respectively (P < 0.0001; P = 0.0005; P < 0.0001). CONCLUSIONS: After ascertaining that core needle biopsy is effectively intralesional, breast hamartomas can be diagnosed with confidence by taking into account the presence of stromal changes, PASH, interlobular distribution of CD34-positive fibroblasts, HMGA2 and hormonal receptor stromal expression.

Expression of neurotensin receptor-1 (NTS1) in primary breast tumors, cellular distribution, and association with clinical and biological factors.

PURPOSE: Neurotensin receptor-1 (NTS1) is increasingly recognized as a potential target in diverse tumors including breast cancer, but factors associated with NTS1 expression have not been fully clarified. METHODS: We studied NTS1 expression using the Tissue MicroArray (TMA) of primary breast tumors from Institut Bergonié. We also studied association between NTS1 expression and clinical, pathological, and biological parameters, as well as patient outcomes. RESULTS: Out of 1419 primary breast tumors, moderate to strong positivity for NTS1 (≥ 10% of tumoral cells stained) was seen in 459 samples (32.4%). NTS1 staining was cytoplasmic in 304 tumors and nuclear in 155 tumors, a distribution which appeared mutually exclusive. Cytoplasmic overexpression of NTS1 was present in 21.5% of all breast tumors. In multivariate analysis, factors associated with cytoplasmic overexpression of NTS1 in breast cancer samples were higher tumor grade, Ki67 ≥ 20%, and higher pT stage. Cytoplasmic NTS1 was more frequent in tumors other than luminal A (30% versus 17.3%; p < 0.0001). Contrastingly, the main "correlates" of a nuclear location of NTS1 were estrogen receptor (ER) positivity, low E&E (Elston and Ellis) grade, Ki67 < 20%, and lower pT stage. In NTS1-positive samples, cytoplasmic expression of NTS1 was associated with shorter 10-year metastasis-free interval (p = 0.033) compared to NTS1 nuclear staining. Ancillary analysis showed NTS1 expression in 73% of invaded lymph nodes from NTS1-positive primaries. CONCLUSION: NTS1 overexpression was found in about one-third of breast tumors from patients undergoing primary surgery with two distinct patterns of distribution, cytoplasmic distribution being more frequent in aggressive subtypes. These findings encourage the development of NTS1-targeting strategy, including radiopharmaceuticals for imaging and therapy.

Predictive Value of MRP-1 in Localized High-Risk Soft Tissue Sarcomas: A Translational Research Associated to ISG-STS 1001 Randomized Phase III Trial.

MRP-1 is implicated in multidrug resistance and was described as prognostic in high-risk patients with soft-tissue sarcoma (STS) in a previous study. The current research aimed to validate MRP-1 prognostic/predictive value in localized sarcomas treated with anthracyclines plus ifosfamide within the ISG-1001 phase III study. In addition, the inhibitory activity on MRP-1 was investigated in preclinical studies to identify new combinations able to increase the efficacy of standard chemotherapy in STS. MRP-1 expression was assessed by IHC in tissue microarrays from patients with STS and tested for correlation with disease-free survival (DFS) and overall survival (OS). In vitro studies tested the efficacy of MRP-1 inhibitors (nilotinib, ripretinib, selumetinib, and avapritinib) in sarcoma cell lines. The effect of combinations of the most active MRP-1 inhibitors and chemotherapy was measured on the basis of apoptosis. MRP-1 was evaluable in 231 of 264 cases who entered the study. MRP-1 expression (strong intensity) was independently associated with worse DFS [HR, 1.78; 95% confidence interval (CI), 1.11-2.83; P = 0.016], in the multivariate analysis, with a trend for a worse OS (HR, 1.78; 95% CI, 0.97-3.25; P = 0.062). In vitro studies showed that the addition of MRP-1 inhibitors (nilotinib or avapritinib) to doxorubicin plus palifosfamide, significantly increased cell death in SK-UT-1 and CP0024 cell lines. MRP-1 is an adverse predictive factor in localized high-risk patients with STS treated with neoadjuvant anthracyclines plus ifosfamide followed by surgery. In vitro findings support the clinical assessment of the combination of chemotherapy and MRP-1 inhibitors as a promising strategy to overcome the drug ceiling effect for chemotherapy.

Superficial CD34-positive fibroblastic tumor and PRDM10-rearranged soft tissue tumor are overlapping entities: a comprehensive study of 20 cases.

AIMS: Superficial CD34-positive fibroblastic tumor (SCD34FT) and PRDM10-rearranged soft tissue tumor (PRDM10-STT) are rare mesenchymal tumors. These lesions have clinicopathological similarities, but their relationship remains controversial. This study aimed to characterise a series of cases of SCD34FT and PRDM10-STT. METHODS AND RESULTS: Ten lesions each of SCD34FT and PRDM10-STT were studied using immunohistochemistry, array-comparative genomic hybridisation (aCGH), RNA sequencing and exome sequencing. Tumors mainly occurred in young adults, were generally small (< 5 cm) and arose predominantly in the superficial soft tissues of the lower extremities. Follow-up data were available in 15 cases (SCD34FT, n = 7, median 16 months; PRDM10-STT, n = 8, median 14 months), local recurrences occurred in four cases (SCD34FT, two of 10; PRDM10-STT, two of 10), while no distant spread was documented. Morphologically, tumors were relatively well-circumscribed and composed of sheets and fascicles of spindle and pleomorphic cells showing low mitotic activity (< 1/mm²) without necrosis. Other findings included: granular cell change, lipoblast-like cells, ectatic blood vessels with fibrinous material, myxoid stromal changes, metaplastic bone and increased mitotic activity (> 1/mm²). All tumors diffusely expressed CD34, while pan-keratin and desmin were commonly seen focally. SynCAM3 was diffusely expressed in 12 cases (SCD34FT, n = 5; PRDM10-STT, n = 7), independently of fusion status. aCGH profiles were 'flat' (PRDM10-STT, n = 4; SCD34FT, n = 2) and exome sequencing showed no recurrent pathogenic mutations (PRDM10-STT, n = 2; SCD34FT, n = 4). Overall, the only morphological features seen exclusively in PRDM10-STT were myxoid stromal changes (three of 10) and metaplastic bone (two of 10). CONCLUSION: We expand the current knowledge on PRDM10-STT and SCD34FT and provide additional evidence for considering them as overlapping entities.

The CDT of Helicobacter hepaticus induces pro-survival autophagy and nucleoplasmic reticulum formation concentrating the RNA binding proteins UNR/CSDE1 and P62/SQSTM1.

Humans are frequently exposed to bacterial genotoxins of the gut microbiota, such as colibactin and cytolethal distending toxin (CDT). In the present study, whole genome microarray-based identification of differentially expressed genes was performed in vitro on HT29 intestinal cells while following the ectopic expression of the active CdtB subunit of Helicobacter hepaticus CDT. Microarray data showed a CdtB-dependent upregulation of transcripts involved in positive regulation of autophagy concomitant with the downregulation of transcripts involved in negative regulation of autophagy. CdtB promotes the activation of autophagy in intestinal and hepatic cell lines. Experiments with cells lacking autophagy related genes, ATG5 and ATG7 infected with CDT- and colibactin-producing bacteria revealed that autophagy protects cells against the genotoxin-induced apoptotic cell death. Autophagy induction could also be associated with nucleoplasmic reticulum (NR) formation following DNA damage induced by these bacterial genotoxins. In addition, both genotoxins promote the accumulation of the autophagic receptor P62/SQSTM1 aggregates, which colocalized with foci concentrating the RNA binding protein UNR/CSDE1. Some of these aggregates were deeply invaginated in NR in distended nuclei together or in the vicinity of UNR-rich foci. Interestingly, micronuclei-like structures and some vesicles containing chromatin and γH2AX foci were found surrounded with P62/SQSTM1 and/or the autophagosome marker LC3. This study suggests that autophagy and P62/SQSTM1 regulate the abundance of micronuclei-like structures and are involved in cell survival following the DNA damage induced by CDT and colibactin. Similar effects were observed in response to DNA damaging chemotherapeutic agents, offering new insights into the context of resistance of cancer cells to therapies inducing DNA damage.

Mature tertiary lymphoid structures predict immune checkpoint inhibitor efficacy in solid tumors independently of PD-L1 expression.

Only a minority of patients derive long-term clinical benefit from anti-PD1/PD-L1 monoclonal antibodies. The presence of tertiary lymphoid structures (TLS) has been associated with improved survival in several tumor types. Here, using a large-scale retrospective analysis of three independent cohorts of cancer patients treated with anti-PD1/PD-L1 antibodies, we showed that the presence of mature TLS was associated with improved objective response rate, progression-free survival, and overall survival independently of PD-L1 expression status and CD8+ T-cell density. These results pave the way for using TLS detection to select patients who are more likely to benefit from immune checkpoint blockade.

Prognostic Role of Inflammasome Components in Human Colorectal Cancer.

(1) We wanted to assess the prognostic impact of inflammasomes involved in gut epithelial homeostasis and the development of human colorectal cancer (CRC). (2) We investigated the expression of inflammasome components in colonic epithelial cells at the protein level in patient tissues, through an immunofluorescence assay. (3) In a cohort of 104 patients, we found that all inflammasome components were downregulated in CRC. Loss of epithelial (but not stromal) expression of NLRP6, caspase-1 and IL-18 was associated with an increased mortality of 72%, 58% and 68% respectively and to disease progression into metastasis. The loss of epithelial and stromal IL-18 but not NLRP6, was associated to lower tumor immune infiltrates in the lymphoid compartment and higher Programmed cell Death receptor 1 (PD-1) expression. Finally, we found that combined downregulation of IL-18 and NLRP6 was associated with a worse outcome. Indeed, 5-year survival rates were 26% for the NLRP6low/IL-18low tumors, compared to 64.4% for the entire cohort. This downregulation was associated with a more advanced disease (p < 0.0001) and a trend to lower lymphoid cell infiltration. (4) We identified critical inflammasome markers that may help in better stratifying patients for prognosis in CRC and could help clinicians to determine which patients may benefit from immunotherapies.

Correction: NFATc2-rearranged sarcomas: clinicopathologic, molecular, and cytogenetic study of 7 cases with evidence of AGGRECAN as a novel diagnostic marker.

An amendment to this paper has been published and can be accessed via a link at the top of the paper.