[Congenital spindle cell/sclerosing rhabdomyosarcoma: a clinicopathological analysis].

Objective: To investigate the clinicopathological features, immunophenotype and molecular genetic characteristics of congenital spindle cell/sclerosing rhabdomyosarcoma. Methods: Sixteen cases (including 10 consultation cases) of congenital spindle cell/sclerosing rhabdomyosarcoma diagnosed at the Beijing Children's Hospital, Capital Medical University, Beijing China, from April 2017 to January 2022 were collected. These cases were evaluated for clinical profiles, histomorphological features, immunophenotype and molecular characteristics. Results: Among the 16 patients, 9 were male and 7 were female. Five cases were present during maternal pregnancy and 11 cases were found immediately after birth. The tumors were located in the chest wall, low back, retroperitoneum, extremities or perineum. The tumors consisted of fasciculated spindle-shaped cells with localized mesenchymal sclerosis and vitreous metaplasia. Immunohistochemistry showed that the tumor cells expressed Desmin, Myogenin, MyoD1, SMA, CD56 and ALK to varying degrees, but not other markers such as CD34, CD99, pan-TRK, S-100 and BCOR. FISH analyses with NCOA2 (8q13) and VGLL2 (6q22) gene breakage probes revealed a breakage translocation in chromosome NCOA2 (8q13) in 4 cases (4/11). In the 6 cases subject to sequencing, a mutation at the p.L122R locus of MYOD1 gene was detected in 1 case (1/6). Two cases were examined by electron microscopy, which showed bundle-arranged myofilaments with some primitive myofilament formation. Five cases were resected with simple surgery, 2 cases were biopsied and followed up with observation only, and 9 cases were treated with surgery and adjuvant chemotherapy. Follow-up was available in 12 cases. At the end of the follow-up, 2 of the 12 patients developed local recurrences and 2 patients survived with disease. Conclusions: Congenital spindle cell/sclerosing rhabdomyosarcoma is a rare subtype of congenital rhabdomyosarcoma. It more commonly occurs in the chest, back and lower limbs of infants than other sites. NCOA2/VGLL2 gene fusion seems to be the most common genetic change. Its prognosis is better than other subtypes of rhabdomyosarcoma and those in adolescents and adults with the same subtype. Analysis and summary of its clinicopathological features can help differentiate it from other soft tissue tumors in infants and children and provide the information for appropriate treatments.

[Hemolytic uremic syndrome complicated with IgA nephropathy: a clinicopathological study].

Objective: To investigate the clinicopathologic characteristics, treatments, outcomes and mechanisms of hemolytic uremic syndrome (HUS) complicated with IgA nephropathy (IgAN). Methods: The clinical manifestations, treatments, prognosis and histopathological features of renal biopsy tissues were analyzed in two cases of HUS complicated with IgAN from Beijing Children's Hospital, Capital Medical University using light microscopy, immunofluorescence detection and electron microscopy. The related literatures were also reviewed. Results: The clinical manifestations were microvascular hemolytic anemia, thrombocytopenia, acute renal impairment with hematuria, proteinuria, and positive anti-H factor antibody. Histological findings confirmed presence of both HUS and IgAN. Histological features included glomerular mesangial and stromal hyperplasia with endothelial cell proliferation, capillary stenosis, arteriolar thickening, and glomerular ischemia and capillary dilatation. Immunofluorescence detection showed diffuse IgA deposition in the glomerular mesangial matrix. Electron microscopy showed proliferation of mesangial and endothelial cells, thickening of the inner layer of the glomerular basement membrane, deposition of massive electronic densification in the mesangial region, and shrinkage of the segmental basement membrane. The two children were very responsive to plasma exchange and steroid treatments. However, their urine protein and occult blood tests remained continuously positive during the follow-up of 5 years 7 months and 8 months respectively. Conclusions: HUS complicated with IgAN is rare. The diagnosis relies on various pathological examinations, which require the combination of light microscopy, immunofluorescence detection and electron microscopy. Plasma exchange and steroid treatments are effective. However, the long-term prognosis is concerning and may relate to pathological grade and secondary factors. The mechanism of connecting HUS and IgAN is unknown, but may be caused by prodromal or secondary factors.

Hsa_circRNA_101036 acts as tumor-suppressor in oral squamous cell carcinoma cells via inducing endoplasmic reticulum stress.

OBJECTIVE: Endoplasmic reticulum (ER) stress has an effect on cancer cell proliferation and survival. TMTC1 has been reported to be involved in cell proliferation and inflammation, and development of ER. Hsa_circRNA_101036 is an exon circRNA formed by splicing of TMTC1 mRNA precursor. This study intends to explore the effect of hsa_circRNA_101036 on the malignant behavior of oral squamous cell carcinoma through endoplasmic reticulum stress. MATERIALS AND METHODS: We firstly evaluated the levels of Hsa_circRNA_101036 in human oral mucous fibroblasts (hOMF), and in several OSCC cell lines, including FaDu, OECM1, SAS, HSC3. Then, we studied the effects of overexpression of Hsa_circRNA_101036 on the cell proliferation, apoptosis, invasion, migration, and cytokine release in OSCC cells. Finally, we evaluated the levels of CHOP that are critical in ER and the ROS levels in OSCC cells. RESULTS: We found that compared with hOMF, a significantly lower mRNA expression of Hsa_circRNA_101036 was found in OECM1 and HSC3 cells. In OECM1 and HSC3 cells, with overexpression of Hsa_circRNA_101036, a significant decrease in cell proliferation, apoptosis, invasion, migration, and cytokine release was found. A significantly increased ROS, as well as increased protein level of CHOP, P38 and Bcl-2, was found in cells with Hsa_circRNA_101036 overexpression. CONCLUSIONS: This study indicated that Hsa_circRNA_101036 may acts as a tumor suppressor in OSCC via regulating the ER in cancer cells.

[Alveolar soft part sarcoma in children: a clinicopathological study of 13 cases].

Objective: To investigate the clinicopathological manifestations, molecular genetic, diagnostic histology and differential diagnosis of alveolar soft part sarcoma (ASPS) in children. Methods: A total of 13 cases of ASPS diagnosed at Beijing Children's Hospital from August 2009 to November 2018 were collected. HE staining, histochemical staining for PAS and D-PAS, immunohistochemical (IHC) staining for TFE3, INI1 and CD68 and florescence in situ hybridization (FISH) for TFE3 gene translocation were performed. Results: There were four males and nine females, age ranged from 1 year and 2 months to 13 years and 8 months (mean 7.8 years); and four patients were under 5 years old. Histologically, the tumors showed a distinctive and characteristic nested or organoid growth pattern (11 cases) or solid, diffuse growth (2 cases). The tumor cells possessed abundant eosinophilic, or glycogen-rich and clear to vacuolated cytoplasm. The chromatin was relatively dispersed, with prominent and pleomorphic nucleoli; mitotic figures were rare. Vascular invasion was frequently seen. IHC staining showed specific nuclear TFE3 staining. The tumor cells were also positive for INI1,CD68 and vimentin; but were negative for MyoD1, Myogenin, CK and S-100 protein. Seven cases showed PAS and D-PAS staining, with fuchsia acicular or rod-shaped crystals in tumor cytoplasm. Nine cases showed TFE3 break-apart signals by FISH. Conclusions: ASPS is a rare soft tissue sarcoma in children. Compared with ASPA in adults, it has both similarities and unique clinicopathologic characteristics. The diagnosis needs to be confirmed by combining clinical, pathologic, IHC and genetic testing.

[Leydig cell hyperplasia of testis in children: a clinicopathological study].

Objective: To investigate the clinical, pathological features and differential diagnosis of testicular Leydig cell hyperplasia (LCH) . Methods: Clinical data, histological features, immunohistochemical findings, ultrastructural characteristics and follow-up data were analyzed in three cases of LCH. The cases were collected from 2011 to 2014 at Beijing Children's Hospital. A literature review was performed. Results: Two males (1.8 years and 2.9 years of age) showed isosexual pseudoprecocity with elevated serum testosterone. Imaging study showed bilateral testicular enlargement with multiple small nodules in the parenchyma. Another 13 years-old patient showed male pseudohermaphroditism and cryptorchism. Gross examination showed the bilateral markedly enlarged testis without discrete lesion. Histologically, LCH was seen in both nodular and diffuse patterns without destruction of seminiferous tubules. Adjacent spermatogenesis was noted. Immunohistochemically, the Leydig cells were positive for inhibin, calretinin and Melan A and ultrastructural analysis showed enriched cytoplasmic endoplasmic reticulum. Two cases had followed up for 7 years. One patient was symptom-free and one was stable. Conclusion: LCH is a rare benign condition, which is easily misinterpreted as testicular tumor or non-neoplastic diseases. Clinical presentation, imaging study and pathological evaluation are required for the diagnosis.

[Clinical and prognostic analysis of single-center multidisciplinary treatment for rhabdomyosarcoma in children].

Objective: To summarize the clinical characteristics, treatment response and prognostic factors of rhabdomyosarcoma (RMS) in children. Methods: The clinical characteristics such as age at diagnosis, primary tumor site, tumor size, pathological type, clinical stage, and risk grouping of 213 RMS patients (140 males and 73 females) treated in Hematology Oncology Center of Beijing Children's Hospital, Capital Medical University, from May 2006 to June 2018 were analyzed retrospectively. The clinical characteristics, overall survival (OS), event free survival (EFS) and prognostic factors of children treated with the Beijing Children's Hospital-Rhabdomyosarcoma (BCH-RMS) regimen were analyzed. Survival data were analyzed by Kaplan-Meier survival analysis, and single factor analysis was performed by Log-Rank test. Results: The diagnostic age of 213 cases was 48.0 months (ranged 3.0-187.5 months), of which 136 cases (63.8%) were younger than 10 years old. The head and neck region was the most common primary site of tumor (30%, 64 cases), followed by the genitourinary tract (26.8%, 57 cases). Among pathological subtypes, embryonal RMS accounted for 71.4% (152 cases), while alveolar RMS and anaplastic RMS accounted for only 26.8% (57 cases) and 1.9% (4 cases), respectively. According to the Intergroup Rhabdomyosarcoma Study Group (IRS), IRS-Ⅲ and Ⅳ accounted for 85.0% (181 cases) of all RMS patients. In all patients, 9.4% (20 cases) patients were divided in to low-risk group, 52.1% (111 cases) patients in to intermediate -risk group, 25.8% (55 cases) patients in to high-risk group, and 12.7% (27 cases) patients in to the central nervous system invasion group, respectively. All patients with RMS received chemotherapy. The cycles of chemotherapy were 13.5 (ranged 5.0-18.0) for patients without event occurrence, while 14.2 (ranged 3.0-30.0) for patients with event occurrence. Among the 213 patients, 200 patients had surgical operation, of whom 103 patients underwent surgery before chemotherapy and 97 patients at the end of chemotherapy, 21 patients had secondary surgical resection. Radiotherapy was performed in 114 patients. The follow-up time was 23.0 months (ranged 0.5-151.0 months) . There were 98 patients with relapsed or progressed disease and 67 patients with death. The median time to progression was 10 months, of which 67 (68.4%) relapse occurred within 1 year and no recurrence occurred after follow-up for more than 5 years. The 3-year EFS and 5-year EFS were (52±4) % and (48±4) %, while the 3-year OS and 5-year OS were (65±4) % and (64±4) % by survival analysis. The 5-year OS of the low-risk, intermediate-risk, the high-risk were 100%, (74±5) %, (48±8) %, and the 2-year OS of the central nervous system invasion group was (36±11) % (χ(2)=33.52, P<0.01). The 5-year EFS of the low-risk, intermediate-risk, the high-risk were (93±6) %, (51±5) %, (36±7) % and the 2-year EFS of the central nervous system invasion group was (31±10) % (χ(2)=24.73, P<0.01) . Survival factor analysis suggested that the OS of children was correlated with age(χ(2)=4.16, P=0.038), tumor TNM stage (χ(2)=22.02, P=0.001), IRS group (χ(2)=4.49, P<0.01) and the risk group (χ(2)=33.52, P<0.01). Conclusions: This study showed that the median age of newly diagnosed RMS patients was 4 years. The head and neck and the genitourinary tract were the most common primary origin of RMS. The OS was low in single-center RMS children. The median time to recurrence was 10 months, and recurrence was rare 3 years later.

[Clinicopathological analysis of 12 cases of children synovial sarcoma].

Objective: To investigate histopathological characteristics, and differential diagnoses of childhood synovial sarcoma. Methods: HE staining, immunohistochemical staining and fusion gene detection by FISH were performed in 12 cases of synovial sarcoma in childhood at Beijing Children's Hospital from 2016 to 2018. Results: There were 6 cases of biphasic type, 1 case of monophasic epithelial type, 3 cases of monophasic spindle cell type and 2 cases of poorly differentiated synovial sarcomas. EMA, CKpan, bcl-2, CD99, TLE1 and CD34 immunostain positivities were observed in 10/12, 9/12, 12/12, 10/12, 10/12 and 0/12 cases respectively. Unique INI1 immunohistochemical staining was observed in 9/12 cases. SS18-SSX gene fusion was detected in 8 of 11 cases by FISH. Conclusions: Synovial sarcoma is rare in children. Histological morphology combined with immunohistochemistry and FISH SS18-SSX fusion gene detection are important for the diagnosis and differential diagnosis of synovial sarcoma in children.

[Langerhans cell histiocytosis in children: clinicopathological and ultrastructural analyses of 345 cases].

Objective: To investigate the clinicopathological and ultrastructural characteristics of Langerhans cell histiocytosis (LCH) in children. Methods: A total of 345 cases of LCH from the Department of Pathology, Beijing Children Hospital from January 2012 to March 2016 were investigated by hematoxylin-eosin stain, EnVision immunohistochemistry and transmission electron microscopy. Results: The rate of primary clinical diagnosis of LCH in children was 46.0%(210/457). Among 345 patients of LCH, 213 were male and 132 were female, the male to female ratio was 1.6∶1.0, and the median age was 21 months (range from 2 days after birth to 13.3 years). There were total 597 lesions, including bony lesions (258, 43.2%), skin lesions (206, 34.5%) , followed by lymph node (16, 2.7%), lung (28, 4.7%), liver (25, 4.2%) and head-neck (50, 8.4%). Single organ system LCH (SS-LCH) was seen in 295 cases (85.5%) and 50 cases (14.5%) presented with multiple organ system involvement LCH (MS-LCH). There was no significant difference in age and gender between SS-LCH and MS-LCH groups. Regarding sites, more lesions were seen in bone and skin in SS-LCH group, in contrast lymph node, lung, liver and head-neck involvements were often seen in MS-LCH group. Immunohistochemically, the expression of CD1a and Langerin was seen in 99.7% (341/342) and 98.8% (338/342) of the cases respectively. The diagnostic rates by light and transmission electron microscopy were 98.8% (341/345) and 97.4% (112/115) respectively (P>0.05). Conclusions: LCH of children occurs predominantly in SS-LCH pattern, frequently involving bone, skin, lymph node, lung and liver and other sites with unique histopathological, immunophenotypical and ultrastructural features. Accurate diagnosis relies on the morphology, immunophenotype and ultrastructural features. Further refinement of specimen processing may improve the accuracy of pathological diagnosis.

Dihydromyricetin induces cell apoptosis via a p53-related pathway in AGS human gastric cancer cells.

The aim of the present study was to determine the anti-proliferative and pro-apoptotic effects of dihydromyricetin (DHM) on the AGS human gastric cancer cells and their underlying mechanisms. The effects of DHM on AGS cells were evaluated by using 3-(4, 5-di-methylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT), lactate dehydrogenase, and Annexin V/propidium iodide (PI) double-staining assays. The underlying mechanisms were determined by using quantitative real-time polymerase chain reaction. The results demonstrated that DHM significantly (P < 0.05) inhibited AGS cell proliferation and induced cell cytotoxicity in a dose- and time-dependent manner. Additionally, Annexin V/PI double-staining assay showed that DHM promoted cell apoptosis in both, early and late stages. Furthermore, DHM also regulated the expression of apoptotic genes such as p53 and B-cell lymphoma-2 (bcl-2) in a dose- and time-dependent manner. In conclusion, this is the first report demonstrating the anticancer and pro-apoptosis effects of DHM on AGS human gastric cancer cells. The results strongly suggest that DHM may be a potential therapeutic candidate for the treatment of gastric cancer.