Increased ACE2 and TMPRSS2 expression in ulcerative colitis.

Ulcerative colitis (UC) is a cryptogenic inflammatory bowel disease, and there is an urgent need to elucidate its pathogenesis. ACE2 and TMPRSS2, the entry molecules of SARS-CoV-2, are reportedly associated with the disease; however, no consensus has been reached yet. In this study, we examined the expression of ACE2 and TMPRSS2 in colon and rectal specimens of UC. We collected colorectal specimens from 60 patients (30 patients with UC and 30 controls from 2018 to 2021) and analyzed the proportion and intensity of ACE2 and TMPRSS2 using immunohistochemistry. The results revealed a significant increase in the proportion of ACE2 expression and the intensity of TMPRSS2 expression in patients with UC. ACE2 and TMPRSS2 expression in UC remained unaffected by the COVID-19 pandemic. We demonstrated that ACE2 and TMPRSS2 are likely involved in the pathogenesis of UC.

Kikuchi Disease After SARS-CoV-2 Vaccination: A Case Report With Immunohistochemical Analyses.

SARS-CoV-2 vaccines have been administered in many countries after the COVID-19 pandemic. Lymphadenopathy is a side effect of SARS-CoV-2 vaccine. We report a rare example of Kikuchi disease in the cervical lymph nodes after SARS-CoV-2 vaccination. A 41-year-old man complained of a swollen neck and fever 9 days after the first dose of SARS-CoV-2 mRNA-1273 vaccine. Computed tomography revealed enlarged cervical lymph nodes. Fine needle aspiration and resection were performed, and the clinicopathological diagnosis was consistent with Kikuchi disease. Histologically, the resected lymph nodes lost their polarity, and many histiocytes were aggregated with karyorrhectic nuclear debris and apoptosis. SARS-CoV-2 positive cells were small lymphocytes detected by immunohistochemistry. This is the first report that demonstrated SARS-CoV-2 expression in Kikuchi disease post-SARS-CoV-2 vaccination.

The Histological Detection of Ulcerative Colitis Using a No-Code Artificial Intelligence Model.

Ulcerative colitis (UC) is an intractable disease that affects young adults. Histological findings are essential for its diagnosis; however, the number of diagnostic pathologists is limited. Herein, we used a no-code artificial intelligence (AI) platform "Teachable Machine" to train a model that could distinguish between histological images of UC, non-UC coloproctitis, adenocarcinoma, and control. A total of 5100 histological images for training and 900 histological images for testing were prepared by pathologists. Our model showed accuracies of 0.99, 1.00, 0.99, and 0.99, for UC, non-UC coloproctitis, adenocarcinoma, and control, respectively. This is the first report in which a no-code easy AI platform has been able to comprehensively recognize the distinctive histologic patterns of UC.

High Infiltration of CD163-Positive Macrophages in Intratumor Compartment Predicts Poor Prognosis in Patients With Upper Urinary Tract Urothelial Carcinoma and Radical Nephroureterectomy.

OBJECTIVES: To investigate the prognostic value of CD68- and CD163-positive macrophages in patients with upper urinary tract urothelial carcinoma (UTUC). PATIENTS AND METHODS: This retrospective study enrolled 50 patients (34 men and 16 women) with UTUC who received radical nephroureterectomy (RNU). We evaluated the expression of CD68 and CD163 in the intratumor compartment by immunohistochemistry. The Kaplan-Meier method and Cox proportional hazards regression model were used to evaluate overall survival (OS), cancer-specific survival (CSS), recurrence-free survival (RFS), and bladder recurrence-free survival (BRFS). RESULTS: High infiltration of CD163-positive macrophages in patients with UTUC was significantly correlated with worse OS, CSS, and RFS (P < .05 for all). Multivariate analysis showed that high infiltration of CD163-positive macrophages was an independent negative prognostic factor of OS and CSS in patients with UTUC who received RNU. Lymphovascular invasion was an independent negative prognostic factor of RFS, and high infiltration of CD68-positive macrophages was an independent positive prognostic factor of BRFS. CONCLUSION: This study indicated that high infiltration of CD163-positive macrophages in the intratumor compartment might be a useful prognostic marker for survival in patients with UTUC who receive RNU. Further, high infiltration of CD68-positive macrophages in the intratumoral compartment might be a useful prognostic marker for bladder recurrence in these patients.

Aberrant MUC Immunohistochemical Expressions in Inflammatory Bowel Diseases.

Ulcerative colitis (UC) and Crohn disease (CD) are cryptogenic inflammatory bowel diseases that are suggestive of aberrant mucin (MUC) expression; however, their relationship remains unclear. Here, we examined aberrant MUC expression in intestinal samples from UC and CD patients in comparison to samples from patients with ischemic colitis and control groups. To study the expression of MUC1 , MUC5AC , and MUC6 in different patient groups, we reviewed the slides stained with hematoxylin and eosin and performed immunohistochemistry. The results revealed that MUC1 was expressed more in the UC group and MUC6 in the CD group. No significant changes were observed in MUC expression in the ischemic colitis group. Overall, we demonstrated changes in MUC expression in UC and CD, which can help in the diagnosis and early clinical management of UC and CD.

EML4-ALK fusion variant.3 and co-occurrent PIK3CA E542K mutation exhibiting primary resistance to three generations of ALK inhibitors.

The ALK inhibitors are promising therapeutic agents against lung cancer harboring ALK fusion genes and are currently under development up to the third generation. However, its therapeutic effects are reported to be affected by differences in ALK variants and co-occurrent mutations. Materials and Methods; We experienced an autopsy case of an ALK-positive lung cancer patient who showed primary resistance to three generations of ALK inhibitors. The poor survival time of the case was 14 months. To reveal the mechanism of primary resistance to three generations of ALK inhibitors, we performed next generation sequencing for 12 specimes obtained from an autopsy with covering whole exons of 53 significantly mutated, lung cancer-associated genes and amplicon-based target RNA sequenceing for the ALK fusion gene. The NGS analysis revealed a rare variant.3 of ALK fusion, in which 30 bp of base was inserted at the end of ALK intron.19 and was associated with EML exon.6 [E6_ins30A20] and a co-occurrent oncogenic PIK3CA E542K mutation in all specimens. Structural analysis of the fusion protein ALK [E6_ins30A20] showed no interferance with the binding of ALK inhibitors to the kinase domain. The NGS analysis of primary and metastatic lesions obtained from an autopsy revealed a co-occurrent oncogenic PIK3CA E542K mutation in all specimens. The constitutive activation of PI3K-Akt signal by PIK3CA E542K mutation occurred downstream of ALK signaling pathway, could lead to primary resistance to ALK inhibitors in all generations.

Bcl-2-negative IGH-BCL2 translocation-negative follicular lymphoma of the thyroid differs genetically and epigenetically from Bcl-2-positive IGH-BCL2 translocation-positive follicular lymphoma.

AIMS: Follicular lymphoma (FL), comprising a minor subset of primary thyroid lymphomas, is divided into two groups based on Bcl-2 expression and IGH-BCL2 translocation. The clinicopathological features exhibited by Bcl-2-negative IGH-BCL2 translocation-negative FL of the thyroid (Bcl-2- /IGH-BCL2- tFL) are different from those of conventional FL; however, its lymphomagenesis remains unclear. Here, we collected samples from seven patients with Bcl-2- /IGH-BCL2- tFL to investigate their epigenetic and genetic aberrations. METHODS AND RESULTS: The immunohistochemical profiles of epigenetic modifiers and the methylation status of histones were examined, including EZH2, MLL2/KMT2D, CBP/CREBBP, EP300, H3K27me3 and H3K4me3, in Bcl-2- /IGH-BCL2- tFL and Bcl-2-positive IGH-BCL2 translocation-positive FL of the thyroid (Bcl-2+ /IGH-BCL2+ tFL). Most Bcl-2- /IGH-BCL2- tFLs retained the positivity of epigenetic modifiers and lower expression of H3K27me3, although Bcl-2+ /IGH-BCL2+ tFLs exhibited aberrant immunohistochemical patterns of EZH2 and CBP/CREBBP and overexpression of H3K27me3. Samples from seven cases were further analysed using targeted sequencing, focusing on the exons of 409 key tumour suppressor genes and oncogenes. Bcl-2- /IGH-BCL2- tFLs do not have pathogenic mutations of epigenetic modifiers, such as EZH2, MLL2/KMT2D, MLL3/KMT2C, EP300 and ARID1A, which have been reported in FLs in the literature, whereas Bcl-2+ /IGH-BCL2+ tFLs are probably pathogenic/pathogenic missense mutations or frameshift mutations of these genes. Additionally, novel mutations in TET2 and EP400 were detected in Bcl-2- /IGH-BCL2- tFLs. CONCLUSIONS: Different genetic and epigenetic abnormalities might be involved in the oncogenesis of Bcl-2- /IGH-BCL2- tFLs from Bcl-2+ /IGH-BCL2+ tFLs and other FLs.

Usefulness of immunohistochemistry to distinguish between secretory carcinoma and acinic cell carcinoma in the salivary gland.

Secretory carcinoma (SC) of the salivary gland is a relatively newly described disease, separate from acinic cell carcinoma (ACC), which frequently displays ETV6-NTRK3 gene fusion. However, the differences between SC and ACC remain unclear. Here, histological reevaluation of 12 formerly diagnosed ACC cases was performed, which yielded a new diagnosis of SC in four cases due to a lack of obvious acinar-like cells. Immunohistochemically, phosphorylated signal transducer and activator of transcription 5 (p-STAT5) was expressed in SC but not in ACC, whereas discovered on GIST-1 (DOG1) was expressed in ACC but not in SC. Molecular analysis was possible in three SC cases, of which two showed the ETV6-NTRK3 fusion transcript on reverse-transcription polymerase chain reaction, as well as breaks in the ETV6 gene on fluorescence in situ hybridization. However, the remaining SC cases did not show this fusion transcript. Recently, several reports have suggested that SC might not be adequately diagnosed if the focus is placed solely on the ETV6-NTRK3 fusion gene due to genetic diversity. In this regard, immunohistochemistry of p-STAT5 and DOG1 is expected to be a useful alternative diagnostic tool to discriminate SC from ACC.

Rapid progressive lung cancers harbouring multiple clonal driver mutations with big bang evolution model.

INTRODUCTION: Next-generation sequencing (NGS) of multiple metastases in an advanced cancer patient reveals the evolutional history of the tumor. The evolutionary model is clinically valuable because it reflects the future course of the tumorigenic process and prognosis of the patient. MATERIALS AND METHODS: We experienced two lung cancer patients whose clinical courses were abruptly deteriorating resulting in very poor prognosis. To investigate the evolutionary model of these patients, we performed targeted sequencing covering whole exons of 53 significantly mutated genes associated with lung cancer of multiple metastases by autopsy. We conducted PyClone analysis to infer subclonal archtecture of multi-lesional samples. RESULTS: The NGS analysis revealed both patients harboring multiple clonal driver mutations. In Case.1, KRAS Q61H, KEAP1 G333C, STK11 K312*, RBM10 Q320* and MGA I1429V and in Case.2, TP53 R337L, TP53 Q192*, PTEN W274C, RB1 P29fs and CREBBP P696L with high allele fraction were detected in all lesions. These mutations were clustered and occupied major population across multi-lesional tumor samples. Our data suggested their lung cancers progressed with punctuated and big bang evolutional model. CONCLUSION: We should pay attention to clinical course of lung cancer patients harboring multiple clonal driver mutations in their primary lesions. Their punctuated and big bang evolutionary process could develop systemic clinically undetectable metastases with an unexpected speed.

Salivary Duct Carcinoma of the Parotid Gland Originating from an Epithelial-Myoepithelial Carcinoma: Report of a Rare Case.

Salivary duct carcinoma (SDC) is a high-grade carcinoma with poor prognosis, especially among various salivary carcinomas. In this study, we report a rare case of SDC of the parotid gland originating from an epithelial-myoepithelial carcinoma (EMC). A 71-year-old Japanese man presented with swelling of the right parotid region and a right facial nerve paralysis for 10 months. He underwent extended total parotidectomy and chemoradiotherapy after the surgery. Histologically, a major part of the tumor was an androgen receptor (AR)-positive, human epidermal growth factor receptor 2 (HER2)-positive, gross cystic disease fluid protein-15 (GCDFP-15)-positive SDC, with a focus of a typical EMC component at the periphery of the lesion. In the transitional area of the two components, inner ductal cells of double-layered ducts showed similar morphology and immunophenotype to SDC. These findings suggest that SDC originated from the inner ductal cells of EMC. Because the tumor included an EMC as a low-grade carcinoma and an SDC as a high-grade carcinoma, we can consider our case as a dedifferentiated carcinoma as well as a hybrid tumor.

Real-time direct measurement of spinal cord blood flow at the site of compression: relationship between blood flow recovery and motor deficiency in spinal cord injury.

STUDY DESIGN: An in vivo study to measure rat spinal cord blood flow in real-time at the site of compression using a newly developed device. OBJECTIVES: To evaluate the change in thoracic spinal cord blood flow by compression force and to clarify the association between blood flow recovery and motor deficiency after a spinal cord compression injury. SUMMARY OF BACKGROUND DATA: Until now, no real-time measurement of spinal cord blood flow at the site of compression has been conducted. In addition, it has not been clearly determined whether blood flow recovery is related to motor function after a spinal cord injury. METHODS: Our blood flow measurement system was a combination of a noncontact type laser Doppler system and a spinal cord compression device. The rat thoracic spinal cord was exposed at the 11th vertebra and spinal cord blood flow at the site of compression was continuously measured before, during, and after the compression. The functioning of the animal's hind-limbs was evaluated by the Basso, Beattie and Bresnahan scoring scale and the frequency of voluntary standing. Histologic changes such as permeability of blood-spinal cord barrier, microglia proliferation, and apoptotic cell death were examined in compressed spinal cord tissue. RESULTS: The spinal blood flow decreased on each increase in the compression force. After applying a 5-g weight, the blood flow decreased to <40% of the precompression level. Complete ischemia was reached using a 20-g weight. After decompression, the blood flow level in the 20-minute complete ischemia group was significantly higher than that in the 40-minute complete ischemia group. The hind-limb motor function in the 40-minute complete ischemia group was significantly less than that in the sham group (without compression), while no significant difference was observed between the 20-minute ischemia group and the sham group. In the 20-minute ischemia group, the rats whose spinal cord blood flow recovery was incomplete showed significant motor function loss compared with rats that completely recovered blood flow. Extensive breakdown of blood-spinal cord barrier integrity and the following microglia proliferation and apoptotic cell death were detected in the 40-minute complete ischemia group. CONCLUSION: Duration of ischemia/compression and blood flow recovery of the spinal cord are important factors in the recovery of motor function after a spinal cord injury.