Clinicopathological, molecular, and prognostic features of colorectal carcinomas with KRAS c.34G>T (p.G12C) mutation.

Evidence indicates that combinations of anti-EGFR antibodies and KRAS p.G12C (c.34G>T) inhibitors can be an effective treatment strategy for advanced colorectal cancer. We hypothesized that KRAS c.34G>T (p.G12C)-mutated colorectal carcinoma might be a distinct tumor subtype. We utilized a prospective cohort incident tumor biobank (including 1347 colorectal carcinomas) and detected KRAS c.34G>T (p.G12C) mutation in 43 cases (3.2%) and other KRAS mutations (in codon 12, 13, 61, or 146) in 467 cases (35%). The CpG island methylator phenotype (CIMP)-low prevalence was similarly higher in KRAS c.34G>T mutants (52%) and other KRAS mutants (49%) than in KRAS-wild-type tumors (31%). KRAS c.34G>T mutants showed higher CIMP-high prevalence (14%) and lower CIMP-negative prevalence (33%) compared with other KRAS mutants (6% and 45%, respectively; p = 0.0036). Similar to other KRAS mutants, KRAS c.34G>T-mutated tumors were associated with cecal location, non-microsatellite instability (MSI)-high status, BRAF wild type, and PIK3CA mutation when compared with KRAS-wild-type tumors. Compared with BRAF-mutated tumors, KRAS c.34G>T mutants showed more frequent LINE-1 hypomethylation, a biomarker for early-onset colorectal carcinoma. KRAS c.34G>T mutants were not associated with other features, including the tumor tissue abundance of Fusobacterium nucleatum (F. animalis), pks+ Escherichia coli, Bifidobacterium, or (enterotoxigenic) Bacteroides fragilis. Among 1122 BRAF-wild-type colorectal carcinomas, compared with KRAS-wild-type tumors, multivariable-adjusted colorectal cancer-specific mortality hazard ratios (95% confidence interval) were 1.82 (1.05-3.17) in KRAS c.34G>T (p.G12C)-mutated tumors (p = 0.035) and 1.57 (1.22-2.02) in other KRAS-mutated tumors (p = 0.0004). Our study provides novel evidence for clinical and tumor characteristics of KRAS c.34G>T (p.G12C)-mutated colorectal carcinoma.

Immunovascular classification of HCC reflects reciprocal interaction between immune and angiogenic tumor microenvironments.

BACKGROUND AND AIMS: Immune cells and tumor vessels constitute important elements in tumor tissue; however, their detailed relationship in human tumors, including HCC, is still largely unknown. Consequently, we expanded our previous study on the immune microenvironment of HCC and analyzed the relationship among the immune microenvironment, inflammatory/angiostatic factor expression, angiogenic factor expression, and tumor vessel findings, including vessels encapsulating tumor clusters (VETC) and macrotrabecular-massive (MTM) patterns. APPROACH AND RESULTS: We classified HCC into four distinct immunovascular subtypes (immune-high/angiostatic [IH/AS], immune-mid/angio-mid [IM/AM], immune-low/angiogenic [IL/AG], and immune-low/angio-low [IL/AL]). IH/AS, IM/AM, and IL/AG subtypes were associated with decreasing lymphocytic infiltration and increasing angiogenic factor expression and VETC/MTM positivity, reflecting their reciprocal interaction in the tumor microenvironment of HCC. IL/AG subtype was further characterized by CTNNB1 mutation and activation of Wnt/ß-catenin pathway. IL/AL subtype was not associated with increased lymphocyte infiltration or angiogenic factor expression. Prognostically, IH/AS subtype and VETC/MTM positivity were independently significant in two independent cohorts. Increased angiogenic factor expression was not necessarily associated with VETC/MTM positivity and poor prognosis, especially when inflammatory/angiostatic milieu coexisted around tumor vessels. These results may provide insights on the therapeutic effects of immunotherapy, antiangiogenic therapies, and their combinations. The potential of evaluating the immunovascular microenvironment in predicting the clinical effect of these therapies in nonresectable HCC needs to be analyzed in the future study. CONCLUSIONS: HCC can be classified into four distinct immunovascular subtypes (IH/AS, IM/AM, IL/AG, and IL/AL) that reflect the reciprocal interaction between the antitumor immune microenvironment and tumor angiogenesis. In addition to its clinicopathological significance, immunovascular classification may also provide pathological insights on the therapeutic effect of immunotherapy, antiangiogenic therapy, and their combination.

Immunovascular microenvironment in relation to prognostic heterogeneity of WNT/ß-catenin-activated hepatocellular carcinoma.

AIM: WNT/ß-catenin-activated hepatocellular carcinoma (W/B subclass HCC) is considered a molecularly homogeneous entity and has been linked to resistance to immunotherapy. However, recent studies have indicated possible heterogeneity in the immunovascular microenvironment in this subclass. We set out to test the hypothesis that specific immunovascular features might stratify W/B subclass HCCs into tumors having distinct aggressive natures. METHODS: In this study, we analyzed 352 resected HCCs including 78 immunohistochemically defined W/B subclass HCCs. The density of tumor-infiltrating CD3+ T cells and the area ratio of vessels encapsulating tumor clusters (VETC) were calculated on tissue specimens. The gene expressions of angiogenic factors were measured by quantitative reverse transcription-polymerase chain reaction. Disease-free survival (DFS) was assessed using multivariable Cox regression analyses. RESULTS: The T-cell density of W/B subclass HCCs was regionally heterogenous within tumor tissues, and focally reduced T-cell density was observed in areas with VETC. VETC-positivity (defined as VETC area ratio greater than 1%) was inversely associated with T-cell infiltration in both W/B subclass and non-W/B subclass HCCs. Fibroblast growth factor 2 (FGF2) gene expression was higher in W/B subclass than in non-W/B subclass HCCs. The VETC-positivity and low T-cell density correlated with increased expression of FGF2 in W/B subclass HCCs. Additionally, VETC-positive HCCs showed significantly shorter DFS in W/B subclass HCCs. CONCLUSIONS: In conclusion, the immune and vascular microenvironments are interrelated and are also correlated with clinicopathological heterogeneity in W/B subclass HCC. These results could inform clinical practice and translational research on the development of therapeutic stratification of HCCs.

Anti-N-methyl-D-aspartate receptor encephalitis with concurrent human herpes virus-6A deoxyribonucleic acid detection: An autopsy case.

We report an autopsy case of anti-N-methyl-D-aspartate (NMDA) receptor (NMDAR) encephalitis with concurrent human herpes virus-6 (HHV-6) A deoxyribonucleic acid (DNA) detection in cerebrospinal fluid (CSF). A 38-year-old previously healthy Japanese man presented with a generalized seizure. Brain magnetic resonance imaging (MRI) findings were unremarkable, but CSF revealed pleocytosis. On Day 11, HHV-6 DNA was detected in CSF, and IgG antibodies against the NR1 subunit of the NMDAR (GluN1) were subsequently detected. Since HHV-6 encephalitis was initially suspected, the patient was treated with foscarnet and ganciclovir, but the HHV-6A copy number increased from 200 (Day 22) to 2000 copies/mL (Day 47), and the therapy was ineffective. As typical symptoms of anti-NMDAR encephalitis developed, we changed the patient's treatment to combat anti-NMDAR encephalitis. He was repeatedly treated with first-line immunotherapy, and GluN1 antibody titer decreased. He was not treated with second-line immunotherapy because of recurrent infections; he died on Day 310. Postmortem examinations did not show systemic tumors. Microscopic examination of the brain revealed only severe neuronal rarefaction in the hippocampal cornu ammonis (CA) 3-4 areas with gliosis. Early initiation of aggressive immunotherapy may be required in a refractory case of anti-NMDAR encephalitis, even with HHV-6A DNA detection, because the significance of this concurrent detection in autoimmune encephalitis remains unclear.

Panaxytriol Inhibits Lipopolysaccharide-Induced Microglia Activation in Brain Inflammation in Vivo.

Brain inflammation is a pathological characteristic of neurodegenerative diseases. In this condition, excessively activated microglia elevate proinflammatory mediator levels. We previously reported that panaxytriol inhibited lipopolysaccharide (LPS)-induced microglia activation in vitro. However, the effects of panaxytriol on microglia activation in vivo require confirmation. In the present study, we found that panaxytriol suppressed both microglia and astrocyte activation by injected LPS intracerebrally to mice with LPS-induced brain inflammation. Panaxytriol was more effective on microglia than astrocytes. Moreover, panaxytriol tended to reduce LPS-induced spontaneous motor activity dysfunction. These results suggested that panaxytriol could improve brain health by suppressing microglia activation in neurodegenerative diseases.

Does the presence of abdominal wall adhesions make gynecologic robotic surgery difficult?

This study aimed to assess the status of abdominal wall adhesions resulting from prior surgeries and their impact on the outcomes of robotic surgery. We retrospectively reviewed clinical information, surgical outcomes, and the status of abdominal wall adhesions in patients who underwent gynecologic robotic surgery at Yamanashi Central Hospital, between April 2018 and March 2023. Abdominal wall adhesions were classified into seven locations and their presence was assessed at each site. Among the 768 cases examined, 196 showed the presence of abdominal wall adhesions. Notably, patients with a history of abdominal surgery exhibited a significantly higher incidence of abdominal wall adhesions than those without such surgical history, although no significant difference was observed in the frequency of adhesions in the upper left abdomen. Patients with a history of gynecologic, gastrointestinal, or biliopancreatic surgeries were more likely to have adhesions at the umbilicus or upper abdomen sites where trocars are typically inserted during robotic surgery. Although cases with abdominal wall adhesions experienced longer operative times than those without, there was no significant difference in estimated blood loss. In 13 cases (1.7%), adjustments in trocar placement were necessary due to abdominal wall adhesions, although none of the cases required conversion to open or conventional laparoscopic surgery. Abdominal wall adhesions pose challenges to minimally invasive procedures, emphasizing the importance of predicting these adhesions based on a patient's surgical history to safely perform robotic surgery. These results suggest that the robot's flexibility proves effective in managing abdominal wall adhesions.

Mirogabalin inhibits scratching behavior of spontaneous model mouse of atopic dermatitis.

Introduction: Atopic dermatitis (AD) is one of the most prevalent intractable chronic itch diseases worldwide. In recent years, new molecular-targeted drugs have emerged, but side effects and economic challenges remain. Therefore, since it is important for AD patients to have a wider range of treatment options, it is important to explore new therapeutic agents. Gabapentinoids, gabapentin and pregabalin, have been shown to be effective for the clinical treatment of several chronic itch. Recently, mirogabalin (MGB) was developed as a novel gabapentinoid. MGB is a drug for neuropathic pain and has a margin of safety between its side effects and the analgesic effect for animal experiments. Herein, we showed that MGB exhibited an antipruritic effect in a mouse model of AD using NC/Nga mice. Methods and results: The oral administration of MGB (10 mg/kg) inhibited spontaneous scratching behavior in AD mice and its effect was dose dependently. Then, when MGB (10 mg/kg) was orally administrated to healthy mice, it did not affect motor function, including locomotor activity, wheel activity, and coordinated movement. Moreover, gabapentin (100 mg/kg) and pregabalin (30 mg/kg), inhibited spontaneous scratching behavior in AD mice and decreased motor function in healthy mice. Furthermore, intracisternal injection of MGB (10 µg/site) significantly suppressed spontaneous scratching behavior in AD mice. Discussion: In summary, our results suggest that MGB exerts an antipruritic effect via the spinal dorsal horn using NC/Nga mice. We hope that MGB is a candidate for a novel therapeutic agent for AD with relatively few side effects.

Spatial Dynamics of T and B Cell Response Predicts Clinical Outcome of Resectable and Unresectable Hepatocellular Carcinoma.

PURPOSE: Immunotherapies have led to a paradigm shift in the treatment of hepatocellular carcinoma (HCC). Studies have revealed the single-cell catalogues of tumor-infiltrating immune cells and the trajectories of their differentiation. Nevertheless, the spatial distribution of these immune cells with distinct phenotypes in tumor microenvironment and their clinicopathological significance in resectable and unresectable HCCs are still largely unclear. EXPERIMENTAL DESIGN: We analyzed the spatial dynamics of intratumoral CD4 and CD8 T cells and their association with B and plasma cells using 283 surgically resected HCCs, 58 unresectable HCC samples before combined immunotherapy (atezolizumab plus bevacizumab [Atezo+Bev]), and autopsy specimens from 50 cases of advanced-stage HCCs through multiplex immunohistochemistry combined with transcriptomic and driver gene mutation analysis. Classification based on the spatial dynamics of T and B cell responses (refined immunosubtype) was developed and its clinicopathological significance was analyzed. RESULTS: We found that stem-like CD4 and CD8 T cells were mainly observed in T cell aggregates. Differentiation of T follicular helper cells were associated with the development of tertiary lymphoid structures, whereas differentiation of CD4 TCXCL13 cells with phenotype resembling T peripheral helper cells were associated with the development of lymphoplasmacytic microenvironment. The refined immunosubtype could predict clinical outcomes of resectable HCC after surgery and unresectable HCC after Atezo+Bev therapy. The immune microenvironment of metastatic lesions tended to reflect those of primary lesions. CONCLUSIONS: We revealed the spatial dynamics of T and B cell response in HCC, which is closely associated with the clinical outcome after surgical resection or Atezo+Bev therapy.

Comparison of surgical outcomes between robot-assisted and conventional laparoscopic hysterectomy for large uterus.

We compared the effectiveness of conventional total laparoscopic hysterectomy (TLH) against robot-assisted total hysterectomy (RAH) in patients with a large uterus. According to the subtype of minimally invasive hysterectomy performed for benign indications, the patients (n = 843) were grouped as follows: TLH (n = 340) and RAH (n = 503). The median operative time (OT) for TLH was 98 min (47-406 min), and the estimated blood loss (EBL) was 50 mL (5-1800 mL). The median OT for RAH was 90 min (43-251 min), and the EBL was 5 mL (5-850 mL), with a significantly shorter OT and a lower EBL in RAH than in TLH. Uterine weight was categorized into four groups in increments of 250 g. The number of cases in each group was 163 (< 250 g), 116 (250-500 g), 41 (500-750 g), and 20 (≥ 750 g) for TLH, and 308 (< 250 g), 137 (250-500 g), 33 (500-750 g), and 25 (≥ 750 g) for RAH. In patients with a uterus < 250 g, there was no significant difference in OT between TLH and RAH, but in patients with a uterus ≥ 250 g, OT tended to be shorter with RAH, which was also true for a uterus ≥ 750 g. The EBL was significantly lower with RAH compared to TLH, regardless of uterine weight. In patients with a large uterus, the advantages of robotic surgery can be utilized, which may lead to a shorter OT and less EBL.

Periostin activates distinct modules of inflammation and itching downstream of the type 2 inflammation pathway.

Atopic dermatitis (AD) is a chronic relapsing skin disease accompanied by recurrent itching. Although type 2 inflammation is dominant in allergic skin inflammation, it is not fully understood how non-type 2 inflammation co-exists with type 2 inflammation or how type 2 inflammation causes itching. We have recently established the FADS mouse, a mouse model of AD. In FADS mice, either genetic disruption or pharmacological inhibition of periostin, a downstream molecule of type 2 inflammation, inhibits NF-κB activation in keratinocytes, leading to downregulating eczema, epidermal hyperplasia, and infiltration of neutrophils, without regulating the enhanced type 2 inflammation. Moreover, inhibition of periostin blocks spontaneous firing of superficial dorsal horn neurons followed by a decrease in scratching behaviors due to itching. Taken together, periostin links NF-κB-mediated inflammation with type 2 inflammation and promotes itching in allergic skin inflammation, suggesting that periostin is a promising therapeutic target for AD.

Detection of Abdominal Lymph Node Metastasis from Pancreatic Neuroendocrine Tumor by Somatostatin Receptor Scintigraphy: Comparison with Somatostatin Receptor Type 2 Immunostaining.

We report a 58-year-old male with a histopathologically proven grade 2 (G2) pancreatic neuroendocrine neoplasm and multiple abdominal node metastases by use of a laparoscopic pancreatic body and tail resection procedure, plus abdominal lymph node dissection. A primary pancreatic tail neuroendocrine tumor sized 20 × 25 mm was detected by contrast-enhanced computed tomography, somatostatin receptor scintigraphy (SRS), and fluorodeoxyglucose positron emission tomography (FDG-PET) examinations and pathologically diagnosed as a pancreatic neuroendocrine tumor (PNET, G2) based on positive immunostaining for somatostatin receptor (SSTR) type 2. Of three metastatic histopathological lymph nodes, two measured 18 × 21 and 10 × 12 mm, respectively, with whole strong SSTR immunostaining showing moderate uptake in SRS findings, whereas the other node, sized 8 × 10 mm, had strong SSTR immunostaining only in a small 6 × 6-mm-sized portion and showed no uptake in SRS findings, likely because of the limited spatial resolution of scintigraphy. On the other hand, only the largest node (18 × 21 mm) was visualized by FDG-PET. SRS may be useful for metastatic lymph node diagnosis based on SSTR immunostaining, though a disadvantage is the spatial resolution limitation.

Mediastinal Cystic Parathyroid Adenoma Diagnosed by Somatostatin Receptor Scintigraphy.

A 71-year-old man complained of nausea and loss of appetite for eight months prior to admission. He was transported to a hospital with disorientation and diagnosed with primary hyperparathyroidism by laboratory examinations. However, ultrasonography, computed tomography, and technetium-99m labeled methoxyisobutyl isonitrile (99mTc-MIBI) with single-photon emission computed tomography did not yield definite results. In contrast, somatostatin receptor scintigraphy successfully identified the lesion responsible for the over-secretion of parathyroid hormone within the middle mediastinum. The tumor was successfully resected by surgery, and a histopathological analysis confirmed the parathyroid adenoma nature of the tumor.