Blastic Indeterminate Dendritic Cell Tumor Associated With Chronic Myelomonocytic Leukemia.

ABSTRACT: Indeterminate dendritic cell tumor (IDCT) is an exceedingly rare neoplasm that can be associated with hematopoietic malignancies. We report a case of multifocal cutaneous blastic indeterminate dendritic cell tumor (BIDCT) in a 75-year-old man with chronic myelomonocytic leukemia showing blastic histiocytoid morphology, positivity for CD1a and S100, and no expression of langerin. We present a literature review on the 11 reported cases of IDCTs/BIDCTs associated with chronic myelomonocytic leukemia (CMML), including this case. The clinicopathological characteristics have been summarized. The IDCT and CMML cells are clonally related in 4 tested cases. Patients with IDCT/BIDCT associated with CMML seem to have worse clinical outcomes compared with patients with IDCT not associated with CMML.

Rosai-Dorfman Disease between Proliferation and Neoplasia.

Rosai-Dorfman disease (RDD) is a rare myeloproliferative disorder of histiocytes with a broad spectrum of clinical manifestations and peculiar morphologic features (accumulation of histiocytes with emperipolesis). Typically, the patient with RDD shows bilateral painless, massive cervical lymphadenopathy associated with B symptoms. Approximately 43% of patients presented with extranodal involvement. According to the 2016 revised histiocytosis classification, RDD belongs to the R group, including familial and sporadic form (classical nodal, extranodal, unclassified, or RDD associated with neoplasia or immune disease). Sporadic RDD is often self-limited. Most RDD needs only local therapies. Nevertheless, a small subpopulation of patients may be refractory to conventional therapy and die of the disease. Recent studies consider RDD a clonal neoplastic process, as approximately 1/3 of these patients harbor gene mutations involving the MAPK/ERK pathway, e.g., NRAS, KRAS, MAP2K1, and, rarely, the BRAF mutation. In addition to typical histiocytic markers (S100/fascin/CD68/CD163, etc.), recent studies show that the histiocytes in RDD also express BCL-1 and OCT2, which might be important in pathogenesis. Additionally, the heterozygous germline mutation involving the FAS gene TNFRSF6 is identified in some RDD patients with an autoimmune lymphoproliferative syndrome type Ia. SLC29A3 germline mutation is associated with familial or Faisalabad histiocytosis and H syndrome.

Uterine Carcinosarcoma: A Case Report and Literature Review.

Uterine carcinosarcomas are rare and extremely aggressive undifferentiated carcinomas which include both carcinomatous and sarcomatous elements. A 52-year-old female presented with heavy irregular menstrual bleeding for several years and new right elbow pain and swelling. Ultrasound and computed tomography showed a large uterine mass with regional and distant metastatic lymphadenopathy and suspicious findings of osseous metastasis to the right elbow. A biopsy confirmed uterine carcinosarcoma, and the patient underwent chemotherapy and then surgical resection of the uterine mass with palliative radiotherapy of the right elbow. The postoperative imaging showed new metastasis, and the patient was scheduled to start on immunotherapy. Considering the highly invasive nature of uterine carcinosarcomas, timely detection of this cancer using characteristic imaging and pathology findings is of extreme importance to improve the patient's survival.

Corrigendum to "Enchondroma protuberans of the hand: A case report" [Radiology Case Reports 15 (2020) 943-946].

[This corrects the article DOI: 10.1016/j.radcr.2020.04.026.].

Enchondroma protuberans of the hand: A case report.

Enchondroma protuberans (EP) is a rare form of enchondroma which demonstrates exophytic growth outside the margins of the bony cortex. A previously healthy 18-year-old male presented with chronic painless palpable mass of the left third finger. Radiograph showed a well-circumscribed expansile lucent lesion in the middle phalanx of the left third finger. The magnetic resonance imaging confirmed an expansile cortical-based lesion extending through the cortex into the soft tissues, which demonstrated high T2 signal with internal foci with low to intermediate signal suggestive of internal chondroid matrix. The patient underwent surgical excision, curettage and bone grafting, and surgical pathology study confirmed the diagnosis of EP. A rare case of EP involving a phalanx of the hand was described in this study. Imaging, particularly magnetic resonance imaging, plays a key role for accurate preprocedural diagnosis.

SMARCA4-deficient uterine sarcoma: A case report and a concise review.

BACKGROUND: SMARCA4-deficient uterine sarcoma (SDUS) is a newly discovered undifferentiated uterine mesenchymal malignancy which has loss of expression of SMARCA4. CASE: A 46-year-old woman presented with heavy irregular vaginal bleeding over the previous 5 months. Computed tomography and magnetic resonance imaging showed a large pelvic mass centered within the uterus, suspicious of malignancy with regional metastatic lymphadenopathy. Biopsy confirmed SDUS and patient underwent chemotherapy. Her symptoms improved 3 months after treatment. CONCLUSION: An extremely rare case of this newly described entity is reported. Recognizing the characteristic imaging and pathology findings of SDUS is essential for an accurate diagnosis, which may affect patient survival.

Intestinal permeability, digestive stability and oral bioavailability of dietary small RNAs.

Impactful dietary RNA delivery requires improving uptake and enhancing digestive stability. In mouse feeding regimes, we have demonstrated that a plant-based ribosomal RNA (rRNA), MIR2911, is more bioavailable than synthetic MIR2911 or canonical microRNAs (miRNAs). Here mutagenesis was used to discern if MIR2911 has a distinctive sequence that aids stability and uptake. Various mutations had modest impacts while one scrambled sequence displayed significantly enhanced digestive stability, serum stability, and bioavailability. To assess if small RNA (sRNA) bioavailability in mice could be improved by increasing gut permeability, various diets, genetic backgrounds and pharmacological methods were surveyed. An intraperitoneal injection of anti-CD3 antibody enhanced gut permeability which correlated with improved uptake of the digestively stable scrambled MIR2911 variant. However, the bioavailability of canonical miRNAs was not enhanced. Similarly, interleukin-10 (IL-10)-deficient mice and mice treated with aspirin displayed enhanced gut permeability that did not enhance uptake of most plant-based sRNAs. This work supports a model where dietary RNAs are vulnerable to digestion and altering gut permeability alone will not impact apparent bioavailability. We suggest that some dietary sRNA may be more digestively stable and methods to broadly increase sRNA uptake requires delivery vehicles to optimize gut and serum stability in the consumer.

Bioavailability of transgenic microRNAs in genetically modified plants.

BACKGROUND: Transgenic expression of small RNAs is a prevalent approach in agrobiotechnology for the global enhancement of plant foods. Meanwhile, emerging studies have, on the one hand, emphasized the potential of transgenic microRNAs (miRNAs) as novel dietary therapeutics and, on the other, suggested potential food safety issues if harmful miRNAs are absorbed and bioactive. For these reasons, it is necessary to evaluate the bioavailability of transgenic miRNAs in genetically modified crops. RESULTS: As a pilot study, two transgenic Arabidopsis lines ectopically expressing unique miRNAs were compared and contrasted with the plant bioavailable small RNA MIR2911 for digestive stability and serum bioavailability. The expression levels of these transgenic miRNAs in Arabidopsis were found to be comparable to that of MIR2911 in fresh tissues. Assays of digestive stability in vitro and in vivo suggested the transgenic miRNAs and MIR2911 had comparable resistance to degradation. Healthy mice consuming diets rich in Arabidopsis lines expressing these miRNAs displayed MIR2911 in the bloodstream but no detectable levels of the transgenic miRNAs. CONCLUSIONS: These preliminary results imply digestive stability and high expression levels of miRNAs in plants do not readily equate to bioavailability. This initial work suggests novel engineering strategies be employed to enhance miRNA bioavailability when attempting to use transgenic foods as a delivery platform.

Anomalous uptake and circulatory characteristics of the plant-based small RNA MIR2911.

Inconsistent detection of plant-based dietary small RNAs in circulation has thwarted the use of dietary RNA therapeutics. Here we demonstrate mice consuming diets rich in vegetables displayed enhanced serum levels of the plant specific small RNA MIR2911. Differential centrifugation, size-exclusion chromatography, and proteinase K treatment of plant extracts suggest this RNA resides within a proteinase K-sensitive complex. Plant derived MIR2911 was more bioavailable than the synthetic RNA. Furthermore, MIR2911 exhibited unusual digestive stability compared with other synthetic plant microRNAs. The characteristics of circulating MIR2911 were also unusual as it was not associated with exosomes and fractionated as a soluble complex that was insensitive to proteinase K treatment, consistent with MIR2911 being stabilized by modifications conferred by the host. These results indicate that intrinsic stability and plant-based modifications orchestrate consumer uptake of this anomalous plant based small RNA and invite revisiting plant-based microRNA therapeutic approaches.

Detection of an Abundant Plant-Based Small RNA in Healthy Consumers.

The mechanisms of delivery of plant small RNAs to consumers must be investigated in order to harness this technology to positively impact biotechnology. Two groups have used honeysuckle (Lonicera japonica) feeding regimes to detect a plant-based small RNA, termed MIR2911, in sera. Meanwhile, numerous groups have failed to detect dietary plant-based small RNAs in consumers. Here we catalog levels of MIR2911 in different herbs, and suggest that in particular herb MIR2911 levels are elevated. Feeding these different herb-based diets to mice, we found MIR2911 levels in the sera and urine were associated with dietary intake levels. Abundance was not the sole determinate of apparent RNA bioavailability, as gavage-feeding large-doses of synthetic MIR2911 permitted only small transient increases in serum levels. Dietary MIR2911 were not modified in circulation by association with the host's RNA-induced silencing complex, as the RNA did not co-immunoprecipitate with AGO2. The stability of dietary MIR2911 in circulation differed from synthesized small RNAs, as tail vein administration of various synthetic plant-based small RNAs resulted in rapid clearance. However, synthetic MIR2911 appeared to be more stable than the other plant miRNAs tested. Notably, this uptake of dietary MIR2911 was not related to perturbations in the host's microbiome or gut permeability. We suggest dietary uptake of MIR2911 is commonplace in healthy consumers, and reproducible detection of plant-based small RNAs in consumers depends on dietary abundance, RNA stability and digestion from within the food-matrix.