PDGFRB and NOTCH3 Mutations are Detectable in a Wider Range of Pericytic Tumors, Including Myopericytomas, Angioleiomyomas, Glomus Tumors, and Their Combined Tumors.

Pericytic tumors are subclassified as myopericytomas, myofibromas, angioleiomyomas, and glomus tumors according to the current World Health Organization classification. These pericytic tumors form a continuous morphologic spectrum, including those with combined morphology. However, to our knowledge, no widely accepted criteria for classifying tumors with combined morphology are available. Recent studies have identified platelet-derived growth factor receptor-beta (PDGFRB) gene mutations in a subset of myofibromas, myopericytomas, and myopericytomatoses but not in angioleiomyomas. NOTCH receptor 3 (NOTCH3) mutations have been reported in a subset of infantile myofibromatosis. To assess their potential role in classifying pericytic tumors, we investigated PDGFRB and NOTCH3 mutations in 41 pericytic tumors of variable morphology, including some combined forms. Our results show these mutations to be present in a variety of pericytic tumors, such as myopericytomas (PDGFRB, 3/11; NOTCH3, 4/11), myopericytomatoses (1/2; 1/2), myofibromas (3/6; 0/6), angioleiomyomas (2/13; 3/13), and glomus tumors (5/9; 1/9). Point mutations were identified in 3 tumors in PDGFRB exon 12 (Y562C, S574F, and G576S), 12 tumors in PDGFRB exon 14 (M655I, H657L, and N666K), and 9 tumors in NOTCH3 exon 25 (A1480S/T, D1481N, G1482S, T1490A, E1491K, G1494S, and V1512A). All PDGFRB mutations and NOTCH3 G1482S, T1490A, and G1494S mutations were classified as "deleterious/damaging" by ≥4 of 6 pathogenicity prediction tools in silico. Five-mutation-positive tumors, including 1 myopericytoma-angioleiomyoma, 2 myopericytomatoses-myofibroma, 1 myofibroma-myopericytoma and 1 angioleiomyoma-myopericytoma, were of combined morphology. Therefore, we found PDGFRB and NOTCH3 mutations to be detectable in a much wider variety of pericytic tumors than previously reported and confirmed myopericytomas, myofibromas, angioleiomyomas, and glomus tumors as members harboring PDGFRB or NOTCH3 mutations. Our results thus suggest that PDGFRB or NOTCH3 mutations are not useful for subclassifying members of the pericytic tumor family.

Preference of grade and lymphovascular invasion over invasive size measurement in stage I lung adenocarcinoma.

AIMS: Although it is necessary to measure the invasive size of lung adenocarcinoma with a lepidic component, it is not uncommon to have trouble in measuring the invasive size of lung adenocarcinoma. This study examined whether there were other stronger prognostic factors than invasive size. METHODS: We characterised the clinicopathological features associated with recurrence-free survival (RFS) of 686 patients with the pathological stage (p-Stage) I lung adenocarcinoma. Moreover, we compared the area under the curve (AUC) values for recurrence between various combinations of pathological-baseline (age & sex & p-Stage based on invasive size) (B(i)) and several prognostic factors, and various combinations of p-baseline based on total tumour size (B(t)) and several prognostic factors. RESULTS: AUC showed no significant differences between B(i) & new International Association for the Study of Lung Cancer grade (G) or vascular invasion (V), and B(t) & G or V. AUC was the highest in B & G & lymphatic invasion (L) & V. RFS was significantly shorter in patients with G3 OR L(+) OR V(+) than in those with G≤2 AND L(-) AND V(-) in each p-Stage based on invasive size (p-Stage(i)) and p-Stage based on total tumour size (p-Stage(t)) (p<0.05), and there were no significant differences in RFS between each p-Stage(i) and p-Stage(t). CONCLUSIONS: In any invasive size or total tumour size of p-Stage I lung adenocarcinoma, G, L and V are more powerful prognostic factors than the size criteria of p-Stage. Therefore, pathologists should focus on these pathological findings.

Identification of fusion transcripts in sarcoma from archival formalin-fixed paraffin-embedded tissues: A next-generation sequencing approach.

Most sarcomas are highly aggressive, and cause necrosis and hemorrhage. The diagnosis of sarcoma is challenging because of the lack of specificity of immunohistochemical staining; however, molecular biological approaches, such as genetic mutation, chromosomal translocation, and gene amplification, are promising. In this study, we extracted RNA from formalin-fixed paraffin-embedded (FFPE) tissue derived from surgically resected specimens of sarcoma stored for various periods and performed next-generation sequencing (NGS) analysis by MiniSeq using the Archer Fusion-Plex Sarcoma Panel. RNA was extracted from 63 FFPE tissue samples, and the degree of RNA degradation was assessed. The number of reads and fragment lengths were evaluated by NGS analysis. RNA extraction and cDNA synthesis were successful in 56 cases and library preparation was possible. Fusion genes were detected in 16 of 63 archived FFPE tissue samples in this study. However, in 18 cases, fragmentation was strong, and high-quality libraries could not be obtained. Nevertheless, comprehensive analysis of fusion genes with high sequence specificity by NGS can be a powerful alternative to reverse transcription-polymerase chain reaction and fluorescence in situ hybridization methods.

Histopathological and epigenetic changes in myocardium associated with cancer therapy-related cardiac dysfunction.

AIMS: Cancer therapy-related cardiac dysfunction (CTRCD) is commonly reported, but its histopathology, mechanisms, and risk factors are not known. We aimed to clarify the histopathology and mechanisms of CTRCD to identify risk factors. METHODS AND RESULTS: We performed myocardial histopathological studies on 13 endomyocardial biopsies from CTRCD patients, 35 autopsied cancer cases with or without cardiac dysfunction, and controls without cancer (10 biopsies and 9 autopsies). Cardiotoxicity risk scores were calculated based on medication; and patient-related risk factors, fibrosis, and cardiomyocyte changes were scored; and p53 and H3K27ac histone modification were evaluated by histological score (H-score). In the biopsy cases, all histopathological changes and the p53 evaluation were significantly higher in the CTRCD group than in the controls [p53 H-score; 63 (9.109) vs. 33 (5.099), P < 0.05]. In patients with a short time between drug and disease onset (<4.2 years), fibrosis and p53 positively correlated (r = 0.76, P < 0.05), and in those with late onset disease (>4.2 years), cellular abnormalities and p53 trended to a positive correlation and cardiotoxicity risk scores and p53 positively correlated (r = 0.95, P < 0.05). A year after biopsy, the short-term group had significant recovery of ejection fraction compared with the long-term group (P < 0.05). The CTRCD group had a significantly worse overall survival prognosis than the control group [hazard ratio 7.61 (95% confidence interval 1.30-44.6), P < 0.05]. Autopsy cases with cancer treatment also had a high grade of histopathological changes, with even more severe changes in patients with cardiac dysfunction, and had increased p53 and H3K27ac expression levels, compared with controls. H-scores of p53 and H3K27ac showed a positive correlation in the CTRCD group in biopsy cases (r = 0.62, P < 0.05) and a positive correlation in autopsy cases. CONCLUSIONS: Our results indicate distinct morphological characteristics in myocardial histopathology associated with CTRCD. p53 and H3K27ac histone modification could be sensitive markers of CTRCD and suggest a mechanistic involvement of epigenetic changes.

Evaluation of DNA/RNA quality from cell block of malignant mesothelioma and lung adenocarcinoma.

Malignant mesothelioma (MM) is a rare and highly lethal tumor that arises from mesothelial tissue on the surface of the chest and abdominal cavity. Cytological examination of body fluids, including pleural fluid and ascites, is essential for the differentiation of malignant mesothelioma from other carcinomas, such as lung and gastrointestinal carcinomas and metastatic tumors. To evaluate the effectiveness of cell block preparation procedures, which are used for immunocytochemical staining and genetic panel analysis of tumor-specific gene mutations, we used various fixatives. We also evaluated the effects of immunostaining, and the quality of nucleic acids for genetic analysis. METHODS: Cell blocks were prepared using the malignant mesothelioma cell lines MESO4 and H226 and non-small cell lung carcinoma cell line HCC78. The cells were fixed using 10% neutral buffered formalin and four different fixatives for liquid cytology. Fixed cells were formed into cell clusters using sodium alginate or centrifugation, and paraffin-embedded cell blocks were prepared. RESULTS: Cell blocks were morphologically evaluated by hematoxylin and eosin and immunocytological staining, and the nucleic acid quality was evaluated by DNA/RNA extraction, qPCR, and next-generation sequence analysis. D2-40 and WT1 staining differed depending on the fixation solution and the cell cluster formation method; however, the degree of nucleic acid degradation was not impaired by any method. CONCLUSION: Although the morphological evaluation of cytology specimens is affected by the method of cell block preparation, it is still useful for nucleic acid extraction and gene panel analysis, as long as there are sufficient amounts of tumor cells.

A Rare Case of Brain Metastasis of Thymic Carcinoma.

BACKGROUND: Thymic carcinoma is a rare cancer that often metastasizes to the liver and kidneys but rarely to the brain. CASE REPORT: We present a rare case of an 81-year-old woman with multiple cerebellar metastases of thymic carcinoma. She was initially diagnosed with stage IVb thymic carcinoma based on biopsy examination of a lesion in the anterior mediastinum. The patient refused to undergo treatment at the time. Six months later, she presented with gait disturbance and nausea. Contrast-enhanced magnetic resonance imaging revealed multiple cerebellar metastases. She underwent craniotomy and resection of the left cerebellar metastasis. Postoperative histological examination confirmed metastasis of the original thymic carcinoma. The patient underwent additional stereotactic radiotherapy for the cavity of the cerebellar metastasis and the small cerebellar metastatic lesions. Seven months after radiotherapy, she died due to progression of the thymic carcinoma. CONCLUSION: We believe that these findings add important information to the literature on this rare entity.

Evaluation and diagnostic value of next-generation sequencing analysis of residual liquid-based cytology specimens of pancreatic masses.

BACKGROUND: Liquid-based cytology (LBC) is a widely used method for processing specimens obtained by endoscopic biopsy. This study evaluated next-generation sequencing (NGS) analysis of LBC specimens to improve the diagnostic accuracy of pancreatic lesions. METHODS: Upon the diagnosis of a suspected pancreatic mass, LBC residues were used retrospectively. The quantity and quality of DNA extracted from residual LBC samples were evaluated, and an NGS analysis targeting 6 genes (KRAS, GNAS, TP53, CDKN2A, SMAD4, and PIK3CA) was performed. RESULTS: The library was prepared from LBC specimens taken from 52 cases: 44 were successful, and 8 preparations failed. An analysis of DNA quantity and quality suggested that the success or failure of NGS implementation depended on both properties. The final diagnosis was achieved by a combination of the pathological analysis of the surgical excision or biopsy material with clinical information. Among the 33 cases of pancreatic ductal adenocarcinoma (PDAC), KRAS, TP53, CDKN2A, and SMAD4 mutations were identified in 31 (94%), 16 (48%), 3 (9%), and 2 (6%), respectively. Among the 11 benign cases, only a KRAS mutation was identified in 1 case. On the basis of NGS results, 18 of 33 PDACs (55%) were classified as highly dysplastic or more, and 10 of 11 benign lesions were evaluated as nonmalignant, which was consistent with the final diagnosis. CONCLUSIONS: NGS analysis using LBC specimens from which DNA of appropriate quantity and quality has been extracted could contribute to improving the assessment of pancreatic tumor malignancies and the application of molecular-targeted drugs.

Correlation of MTAP Immunohistochemistry With CDKN2A Status Assessed by Fluorescence In Situ Hybridization and Clinicopathological Features in CNS WHO Grade 2 and 3 Meningiomas: A Single Center Cohort Study.

CDKN2A homozygous deletion has occasionally been reported in atypical and anaplastic meningiomas and is considered as one of the genetic alterations commonly involved in their recurrence and malignant progression. Methylthioadenosine phosphorylase (MTAP) immunohistochemistry is a promising surrogate marker for CDKN2A homozygous deletion in different cancers but has not been examined in meningiomas. We performed CDKN2A FISH and MTAP immunohistochemistry on specimens from 30 patients with CNS WHO grade 2 (n = 27) and 3 (n = 3) meningiomas, including specimens from primary and recurrent tumors and then determined whether MTAP immunohistochemistry correlated with CDKN2A homozygous deletion and clinicopathological features. CDKN2A homozygous deletion was detected in 12% (3/26) of CNS WHO grade 2 and 67% (2/3) of CNS WHO grade 3 meningiomas; 3 cases exhibited temporal and/or spatial heterogeneity. MTAP loss was in excellent concordance with CDKN2A homozygous deletion (sensitivity; 100%, specificity; 100%). MTAP loss/CDKN2A homozygous deletion correlated with cellular proliferation (mitotic rate; p = 0.001, Ki-67 labeling index; p = 0.03) and poor prognosis (overall survival; p = 0.01, progression free survival; p < 0.001). Thus, MTAP immunostaining can be a surrogate marker for CDKN2A homozygous deletion in meningiomas, and MTAP loss/CDKN2A homozygous deletion may be an important prognostic factor for meningiomas.

Clinical Impact of Subclinical Interstitial Fibrosis or Tubular Atrophy in 1-Hour Allograft Biopsy for Remnant Renal Function in Living Kidney Donors: A Prospective Observational Study.

BACKGROUND: Preservation of remnant renal function (RRF) is one of the major concerns among living kidney donors (LKDs). A comprehensive assessment is needed to predict the RRF. In this prospective study, we investigated the roles of histologic findings from a 1-hour allograft biopsy in predicting the RRF. METHODS: Our prospective study included 116 LKDs who underwent donor nephrectomy (DN) at our institute. Clinical and radiographic data were obtained from their medical charts. Renal volume parameters were calculated using the preoperative computed tomographic images in the volume analyzer SYNAPSE VINCENT image analysis system. Tissues obtained from allograft biopsy were examined. RRF was defined as the estimated glomerular filtration rate (eGFR) 12 months after DN. RESULTS: Of 116 LKDs, 95 were finally evaluated. The median age of the LKDs at DN and the preoperative eGFR were 57 years and 80.0 mL/min/1.73 m2, respectively. In the histologic analysis, 68 allografts (71.6%) had nonspecific findings involving the glomerulus, vessel, and tubulointerstitium. Interstitial fibrosis or tubular atrophy (IF/TA) was the only significant predictive factor for RRF (P = .039). No significant association was found between renal volume parameters and IF/TA, whereas remnant renal volume adjusted by body weight (RRV/BW) tended to be relatively correlated with IF/TA (P = .072). Furthermore, LKDs with subclinical IF/TA tended to have decreased RRV/BW compared with those without subclinical IF/TA (P = .088). CONCLUSIONS: Our findings suggested that the presence of IF/TA could be a predictive factor for RRF after DN. Further research establishing the predictive model for RRF is warranted to improve the outcomes of LKDs.

Diffuse large B-cell lymphoma (DLBCL) with significant intravascular invasion. Close resemblance of its clinicopathological features to intravascular large B-cell lymphoma, but not to DLBCL-not otherwise specified.

Intravascular large B-cell lymphoma (IVLBCL) is defined by the World Health Organization (WHO) Classification as one type of extranodal large B-cell lymphoma and it is characterized by the selective growth of lymphoma cells within blood vessels with minimal extravascular invasion. According to the criteria, however, several reported cases of IVLBCL with significant extravascular invasion cannot be classified as IVLBCL. The purpose of the present study was to assess the clinicopathological significance of the WHO criteria for IVLBCL. We characterized clinical, histopathological, and immunohistochemical features of 11 patients with extranodal diffuse large B-cell lymphoma (DLBCL) with significant intravascular invasion (DLBCL-IV), and statistically compared their features with those of 11 patients with IVLBCL and 15 patients with extranodal DLBCL with virtually no intravascular invasion (DLBCL-noIV). When compared with the DLBCL-noIV group, the DLBCL-IV group was characterized by significantly higher rates of splenomegaly, hemophagocytosis, advanced stage disease, and CD5 expression; higher average platelet count, serum lactate dehydrogenase level, and serum ferritin level. Progression-free survival was significantly shorter in the DLBCL-IV group than the DLBCL-noIV group. In contrast, there were no significant differences in clinicopathological features between the DLBCL-IV and the IVLBCL groups. Our study suggests that DLBCL-IV should be regarded as IVLBCL-related.

TRAF7 mutations and immunohistochemical study of uterine adenomatoid tumor compared with malignant mesothelioma.

Adenomatoid tumors (ATs) are benign mesothelial tumors with a good prognosis and usually occur in female and male genital tracts, including in the uterus. ATs are genetically defined by tumor necrosis factor receptor-associated factor (TRAF) 7 mutations, and a high number of AT cases show immunosuppression. On the other hand, malignant mesotheliomas (MMs) are malignant mesothelial tumors with a very poor prognosis. Genetic alterations in TRAF, methylthioadenosine phosphorylase(MTAP), and BRCA-associated nuclear protein 1 (BAP1) in ATs derived from the uterus and MMs of pleural or peritoneal origin were compared by gene sequence analysis or immunohistochemical approaches. Formalin-fixed paraffin-embedded tissues derived from patients were used for immunohistochemical staining of L1 cell adhesion molecule (L1CAM), BAP1, MTAP, and sialylated protein HEG homolog 1 (HEG1) in 51 uterine AT cases and 34 pleural or peritoneal MM cases and for next-generation sequencing of the TRAF7 gene in 44 AT cases and 21 MM cases. ATs had a significantly higher rate of L1CAM expression than MMs, whereas MMs had a significantly higher rate of loss of MTAP and BAP1 expression than ATs. There was no difference in the rate of HEG1 expression between the tumor types. Most of the ATs (37/44; 84%) had somatic mutations in TRAF7, but none of the MMs had somatic mutations in TRAF7 (0/21; 0%). In addition, a low number of AT cases were associated with a history of immunosuppression (9/51; 17.6%). TRAF7 mutation is one of the major factors distinguishing the development of AT from MM, and immunosuppression might not be associated with most AT cases.

Gastritis cystica profunda is associated with aberrant p53 and Epstein-Barr virus in gastric cancer: A clinicopathological, immunohistochemical and in situ hybridization study.

Gastritis cystica profunda (GCP) is a lesion characterized by cystic gastric glands within the submucosa. Some studies have reported that GCP is a precancerous lesion. Here, we investigated the association between GCP and gastric cancer. Gastric cancer specimens were taken from 1432 patients undergoing surgery or endoscopic submucosal resection and were classified as GCP or non-GCP. The clinicopathological features, immunohistochemistry and in situ hybridization expression of p53, Ki-67, KCNE2, Epstein-Barr virus (EBV) and programmed death ligand 1 (PD-L1) were compared between the two groups, as well as between GCPs and normal pyloric glands. One hundred and eighty patients (12.6%) had GCPs. In the GCP group, no cancerous lesions were found within the GCPs, but 13% were linked to GCPs and 60.2% were located above or near GCPs. Aberrant p53 expression, EBV-positive cancer cells and PD-L1 scores were significantly higher in the GCP group. The p53 score and Ki-67 labelling index were significantly higher and the KCNE2 score was significantly lower in GCPs than in pyloric glands. Although we suggest GCP is paracancerous, GCP has high proliferation activity and gastric cancer with GCP is associated with aberrant p53 and EBV. GCP is associated with aberrant p53 expression and EBV.

A case of a rare non-invasive lung adenocarcinoma.

BACKGROUND: According to the WHO classification, adenocarcinoma in situ (AIS) is a localised small (≤3 cm) adenocarcinoma whose growth is restricted to neoplastic cells along pre-existing alveolar structures, lacking stromal, lymphovascular, or pleural invasion. There is no evidence to define AIS as having a tumour size of ≤3 cm. It is extremely rare for adenocarcinomas with pure lepidic growth lacking invasion to be >3.0 cm. The biological characteristics of these large AISs should be revealed. PRESENTATION OF CASE: The patient was an 82-year-old asymptomatic woman. Chest computed tomography showed a 6-cm-diameter pure ground-glass opacity in the left lower lung. The patient underwent lobectomy. On histologic examination, the tumour was restricted to neoplastic cells along pre-existing alveolar structures, lacking stromal, vascular, alveolar space, and pleural invasion. Papillary patterns were absent. Initially, the histopathological diagnosis was AIS, but the total tumour diameter exceeded 3 cm. The final pathological diagnosis was lepidic adenocarcinoma lacking an invasive component and harbouring an EGFR exon 20 insertion V774_C775insHV mutation using next-generation sequencing (NGS). CONCLUSION: We report a rare case of lepidic adenocarcinoma with a total tumour diameter of 6 cm and without an invasive component. Although EGFR mutations are oncogenic driver mutations, AISs have fewer EGFR mutations than invasive adenocarcinomas do. An adenocarcinoma that progresses to AIS, not stepwise progression, might have uncommon mutations and might be another type of adenocarcinoma. NGS could be useful for detecting uncommon genes that reveal the biological characteristics of AIS, and may contribute to the validation of next TNM classification.

Evaluation of DNA and RNA quality from archival formalin-fixed paraffin-embedded tissue for next-generation sequencing - Retrospective study in Japanese single institution.

Genetic analysis on formalin-fixed paraffin-embedded (FFPE) tissue specimens has become a mainstream method, from conventional direct sequencing to comprehensive analysis using next-generation sequencing (NGS). In this study, we evaluated the quality of DNA and RNA extracted from FFPE sections, derived from surgical specimens of different tumor types. Electrophoresis was performed using a 4200 TapeStation to evaluate DNA and RNA fragmentation. DNA Ct values were higher and significantly increased over a period of 4 years compared with those from cell lines or frozen tissues. The RNA integrity number equivalent (RIN) ranged from 1 to 4.1 and DV200 ranged from 7.3 to 81%. Twelve of the 108 cases were analyzed by NGS using the AmpliSeq Cancer HotSpot Panel v2 on a Miniseq system. A sufficient number of reads and coverage were obtained in all cases. Our results revealed that NGS analysis was sufficient for FFPE-derived DNA within 4 years of preservation. Conversely, approximately 20% of the RNA derived from FFPE within 4 years from the collection could be inappropriate for gene analysis based on RIN and DV200. It was suggested that FFPE would be adequate for genetic analysis, although it is desirable to store frozen specimens for the tumor tissues to be subjected to genetic analysis.

Complement activation is associated with crescent formation in IgA nephropathy.

IgA nephropathy (IgAN) is common chronic glomerulonephritis with variable prognosis, ranging from minor urinary abnormalities to end-stage renal disease. The revised Oxford classification of IgAN explains that cellular/fibrocellular crescents are associated with poor renal prognosis, proposing an extension to the MEST-C score. C3 immunofluorescent staining follows a distribution similar to IgA staining. Therefore, complement activation was reported to play a pivotal role in IgAN pathogenesis. This study included 132 IgAN patients diagnosed by renal biopsies. The clinical parameters at the time of the biopsies were obtained from patient data records. We classified the patients into C ≥ 1 and C0 groups, and compared clinical, light microscopic, and immunofluorescent features. In the C ≥ 1 group, 2 (1.5%) and 31 (23.5%) patients were assigned to C2 and C1, respectively. The remaining 99 patients (75%) were classified as C0. The C ≥ 1 group had lower average age and rate of hypertension, and higher score of urinary occult blood and E score. The C ≥ 1 group had significantly higher average immunofluorescence scores for IgA, C5b-9, mannose-associated serine protease (MASP) 1/3, MASP2, properdin, factor B, and kappa. The steroid use rate was significantly higher in the C ≥ 1 group. During the follow-up period of 2.90 years on average, the rate of renal dysfunction was not significantly different between groups. Crescent formation in IgAN was associated with activation of the lectin and alternative pathways. The C ≥ 1 group had significantly increased use of steroids, which probably caused comparable renal function during the follow-up period.

HEG1-responsive microRNA-23b regulates cell proliferation in malignant mesothelioma cells.

Malignant mesothelioma (MM) is a fatal tumor, and the absence of a specific diagnostic marker and/or a pathogenic molecule-targeting drug is a major issue for its pathological diagnosis and for targeting therapy. The molecular target of MM has not been elucidated because of unknown survival, death, and cytotoxic signals in MM. HEG homolog 1 (HEG1) is a mucin-like membrane protein that contains epidermal growth factor-like domains, and it plays an important role in cancers through aberrant signaling, including that during cell adhesion, as well as through protection from invasion of tumor cells. HEG1 expression supports the survival and proliferation of MM cells. In this study, functional analysis of HEG1 and microRNAs using MM cell lines (H226, MESO4, H2052) was performed. The MTS assay revealed that cell proliferation was significantly reduced upon transient transfection with microRNA-23b (miR-23b) inhibitor and/or HEG1 siRNA. The Annexin V assay revealed that apoptosis was induced upon suppression of miR-23b and/or HEG1. Western blotting showed that the autophagy-related protein LC3-II was induced upon suppression of miR-23b and/or HEG1. These results revealed that miR-23b contributes to HEG1-dependent cell proliferation through evasion of cytotoxicity induced by apoptosis and autophagy in MM cells. HEG1-dependent/mediated miR-23b signaling may therefore be a potential target for MM diagnosis and therapy.

Immunohistochemical Reappraisal Regarding the Frequency of Primary Salivary Gland Follicular Lymphoma.

Although it has been described that extranodal marginal zone lymphomas of mucosa-associated lymphoid tissue (MALT lymphomas) are the most common type among primary salivary gland lymphomas (SGLs), some studies revealed that the frequency of follicular lymphomas (FLs) was as high as that of MALT lymphomas. However, it has been reported that many of these FLs may have developed in lymph nodes attached to the capsule of the glands or intraglandular lymph nodes. Clinical, histological, immunohistochemical, and cytogenetic features of 11 SGL cases, which were extracted from our surgical pathology file consisting of consecutive pathology cases, were reevaluated to further characterize whether they were actually primary SGLs. There were 3 (27%) cases of FLs, 5 (46%) cases of MALT lymphomas, and 3 (27%) cases of diffuse large B-cell lymphomas. Although all of our FL cases fulfilled the criteria of primary SGL, tumors of several FL cases were surrounded by podoplanin (by D2-40)-positive elongated vessels or linear structures indicative of nodal subcapsular sinuses (open or remnant). This finding would support the aforementioned possibility, and podoplanin staining is necessary before concluding that a FL is a primary SGL.

NACC1, as a Target of MicroRNA-331-3p, Regulates Cell Proliferation in Urothelial Carcinoma Cells.

The nucleus accumbens-associated protein 1 (NACC1) is a transcription factor constitutively expressed in the urothelium, where it regulates cell growth, senescence, autophagy, and epithelial-mesenchymal transition. microRNA (miRNA) constitutes a class of small non-coding RNAs which are involved in cell proliferation, differentiation, and progression of tumors. miRNAs and their target molecules are utilized for molecular diagnosis of urothelial carcinoma. NACC1 is one of several putative target molecules of miR-331-3p, and is associated with cell proliferation in cancers such as prostate and cervical cancer. Functional experiments involving miR-331-3p and its target molecule NACC1 were conducted using the urothelial carcinoma (UC) cell lines, T24, UMUC6, and KU7. Furthermore, quantitative reverse transcription polymerase chain reaction and immunostaining were performed to evaluate the expression of NACC1 in UC derived from transurethral resection of bladder tumor (TUR-Bt) specimens. The methane thiosulfonate (MTS) assay revealed that cell proliferation was significantly reduced after transient transfection of miR-331-3p precursor and/or NACC1 siRNA in UC cells. Cell senescence via cell cycle arrest at the G1 phase was induced by NACC1 inhibition. On the other hand, suppression of NACC1 induced cell migration and invasion abilities. Immunohistochemical analysis of TUR-Bt specimens revealed that over 70% of UC cells presented strongly positive results for NACC1. In contrast, normal urothelial cells were weakly positive for NACC1. It was also found that NACC1 expression was lower in invasive UC cells than in non-invasive UC cells. Loss of NACC1 induced vessel invasion in invasive UC tissues. The present results indicate that NACC1 regulated by miR-331-3p contributes to cell proliferation, and is involved in cell migration and invasion. This suggests that NACC1 can serve as a potential target molecule for the prediction and prognosis of UC, and can contribute to effective treatment strategies.

Complement activation associated with ADAMTS13 deficiency may contribute to the characteristic glomerular manifestations in Upshaw-Schulman syndrome.

INTRODUCTION: Upshaw-Schulman syndrome (USS) is a congenital form of thrombotic thrombocytopenic purpura (TTP) associated with loss-of-function mutations in the ADAMTS13 gene, possibly leading to aberrant complement activation and vascular injury. However, USS is extremely rare, and there have been no systematic studies correlating histopathological severity with local ADAMTS13 expression and complement activation. MATERIALS AND METHODS: Here, we compared histopathological features, ADAMTS13 immunoreactivity, and immunoreactivity of complement proteins C4d and C5b-9 among renal biopsy tissues from five USS cases, ten acquired TTP cases, and eleven controls. RESULTS: Pathological analysis revealed chronic glomerular sclerotic changes in the majority of USS cases (4 of 5), with minor glomerular pathology in the remaining case. In two of these four severe cases, more than half of the glomerular segmental sclerosis area was localized in the perihilar region. The average number of ADAMTS13-positive cells per glomerulus was significantly lower in USS cases than controls (p < 0.05). Conversely, C4d staining was significantly more prevalent in the glomerular capillary walls of USS cases than controls (p < 0.05), while C5b-9 staining did not differ significantly among groups. CONCLUSIONS: These findings suggest that the severity of glomerular injury in USS is associated with deficient ADAMTS13 expression and local complement activation, particularly in vascular regions with higher endothelial shear stress. We suggest that C4d immunostaining provides evidence for complement-mediated glomerular damage in USS.