Live imaging of avian epiblast and anterior mesendoderm grafting reveals the complexity of cell dynamics during early brain development.

Despite previous intensive investigations on epiblast cell migration in avian embryos during primitive streak development before stage (st.) 4, this migration at later stages of brain development has remained uninvestigated. By live imaging of epiblast cells sparsely labeled with green fluorescence protein, we investigated anterior epiblast cell migration to form individual brain portions. Anterior epiblast cells from a broad area migrated collectively towards the head axis during st. 5-7 at a rate of 70-110 µm/h, changing directions from diagonal to parallel and forming the brain portions and abutting head ectoderm. This analysis revised the previously published head portion precursor map in anterior epiblasts at st. 4/5. Grafting outside the brain precursor region of mCherry-expressing nodes producing anterior mesendoderm (AME) or isolated AME tissues elicited new cell migration towards ectopic AME tissues. These locally convergent cells developed into secondary brains with portions that depended on the ectopic AME position in the anterior epiblast. Thus, anterior epiblast cells are bipotent for brain/head ectoderm development with given brain portion specificities. A brain portion potential map is proposed, also accounting for previous observations.

Chicken embryo cultures in the dorsal-upward orientation for the manipulation of epiblasts.

Chicken embryos have many advantages in the study of amniote embryonic development. In particular, culture techniques developed for early-stage embryos have promoted the advancement of modern developmental studies using chicken embryos. However, the standard technique involves placing chicken embryos in the ventral-upward (ventral-up) orientation, limiting manipulation of the epiblast at the dorsal surface, which is the primary source of ectodermal and mesodermal tissues. To circumvent this limitation, we developed chicken embryo cultures in the dorsal-up orientation and exploited this technique to address diverse issues. In this article, we first review the history of chicken embryo culture techniques to evaluate the advantages and limitations of the current standard technique. Then, the dorsal-up technique is discussed. These technological discussions are followed by three different examples of experimental analyses using dorsal-up cultures to illustrate their advantages: (1) EdU labeling of epiblast cells to assess potential variation in the cell proliferation rate; (2) migration behaviors of N1 enhancer-active epiblast cells revealed by tracking cells with focal fluorescent dye labeling in dorsal-up embryo culture; and (3) neural crest development of mouse neural stem cells in chicken embryos.

High serum proteinase-3 levels predict poor progression-free survival and lower efficacy of bevacizumab in metastatic colorectal cancer.

BACKGROUND: To improve the prognosis of patients with metastatic colorectal cancer (mCRC), investigating predictive biomarkers of their prognosis and chemotherapeutic responsiveness is necessary. This study aimed to analyze the clinical significance of serum proteinase-3 (PRTN3) as a predictor for prognosis and chemosensitivity, especially to bevacizumab therapy, in mCRC. METHODS: This single-center retrospective observational study enrolled 79 patients with mCRC in our hospital and 353 patients with colorectal cancer in the TCGA database. Preoperative serum PRTN3 levels were measured using an enzyme-linked immunosorbent assay. The clinicopathological characteristics and prognosis according to serum PRTN3 levels were then evaluated. PRTN3 expression in tumor and stromal cells was evaluated immunohistochemically. The impact of PRTN3 levels on angiogenesis and bevacizumab sensitivity was evaluated using the tube formation assay. RESULTS: Serum PRTN3 levels were an independent poor prognostic factor for progression-free survival (PFS) (hazard ratio, 2.082; 95% confidence interval, 1.118-3.647; P=0.010) in patients with mCRC. Similarly, prognostic analysis with TCGA data sets showed poorer overall survival in patients with PRTN3 expression than that in patients without PRTN3 expression, especially in patients with stage IV. Immunohistochemical analysis of resected specimens revealed that stromal neutrophils expressed PRTN3, and their expression level was significantly correlated with serum PRTN3 levels. Interestingly, the effectiveness of first-line chemotherapy was significantly poorer in the high serum PRTN3 level group. High serum PRTN3 was significantly associated with poor PFS (hazard ratio, 3.027; 95% confidence interval, 1.175-7.793; P=0.0161) in patients treated with bevacizumab, an anti-angiogenic inhibitor. The tube formation assay revealed that PRTN3 administration notably augmented angiogenesis while simultaneously attenuating the anti-angiogenic influence exerted by bevacizumab therapy. CONCLUSIONS: Serum PRTN3 levels could be a novel predictive biomarker of PFS of first-line chemotherapy, especially for bevacizumab therapy, in patients with mCRC.

Steroid-resistant minimal change nephrotic syndrome associated with thymoma treated effectively with rituximab following thymectomy and cyclosporine: a case report.

BACKGROUND: Minimal change nephrotic syndrome (MCNS) can be complicated by thymoma; however, no standard therapy for thymoma-associated MCNS has yet been established. We herein describe a case of steroid-resistant MCNS associated with thymoma, treated effectively with rituximab. CASE PRESENTATION: A 71-year-old Japanese man was referred to our department with severe proteinuria (20 g/gCr). Renal biopsy showed minimal change disease and computed tomography revealed an anterior mediastinal mass. Based on these findings, he was diagnosed with thymoma-associated MCNS. He was treated with oral prednisolone (50 mg/day) and cyclosporine, and underwent thymectomy and plasma exchange. However, no improvement in proteinuria was observed. He therefore received intravenous rituximab 500 mg, resulting in a marked decrease in proteinuria from 5328 to 336 mg/day after 1 week. CONCLUSIONS: This case suggests that rituximab might be an effective therapy in patients with steroid-resistant MCNS associated with thymoma.

IL-6 Levels Correlate with Prognosis and Immunosuppressive Stromal Cells in Patients with Colorectal Cancer.

BACKGROUND: The prognosis for patients with colorectal cancer (CRC) is determined by tumor characteristics as well as the host immune response. This study investigated the relationship between an immunosuppressive state and patient prognosis by evaluating the systemic and tumor microenvironment (TME) interleukin (IL)-6 levels. METHODS: Preoperative serum IL-6 levels were measured using an electrochemiluminescence assay. Expression of IL-6 in tumor and stromal cells was evaluated immunohistochemically in 209 patients with resected CRC. Single-cell analysis of tumor-infiltrating immune cells was performed using mass cytometry in 10 additional cases. RESULTS: Elevated serum IL-6 levels were associated with elevated stromal IL-6 levels and a poor prognosis for patients with CRC. High IL-6 expression in stromal cells was associated with low-density subsets of CD3+ and CD4+ T cells as well as FOXP3+ cells. Mass cytometry analysis showed that IL-6+ cells among tumor-infiltrating immune cells were composed primarily of myeloid cells and rarely of lymphoid cells. In the high-IL-6-expression group, the percentages of myeloid-derived suppressor cells (MDSCs) and CD4+FOXP3highCD45RA- effector regulatory T cells (eTreg) were significantly higher than in the low-IL-6-expression group. Furthermore, the proportion of IL-10+ cells in MDSCs and that of IL-10+ or CTLA-4+ cells in eTregs correlated with IL-6 levels. CONCLUSION: Elevated serum IL-6 levels were associated with stromal IL-6 levels in CRC. High IL-6 expression in tumor-infiltrating immune cells also was associated with accumulation of immunosuppressive cells in the TME.

[A Severe Case of Bleeding from Duodenal Invasion Due to Co-Morbid IPMC with Arcuate Ligament Syndrome and IPDA Aneurysm].

An 81-year-old man with a history of left hemiplegia due to a cerebral hemorrhage was admitted to a clinic because of tarry stools. Endoscopic findings revealed an ulcerative lesion with hemorrhage in the descending duodenum. The patient was transferred to our hospital for treatment. Because endoscopic hemostasis was impossible, interventional radiology(IVR) hemostasis was performed using coil embolization for the feeding artery. Simultaneously, angiography showed stenosis of the root of the celiac axis due to arch ligament syndrome and an aneurysm of the inferior pancreaticoduodenal artery (IPDA). Due to the risk of rebleeding, subtotal stomach-preserving pancreatoduodenectomy was performed after the patient's overall condition had stabilized. Despite dissecting the arcuate ligament, the hepatic artery flow did not improve. Hence, a direct arterial anastomosis between the middle colic artery and the gastroduodenal artery was performed. Furthermore, due to the proximity of the IPDA aneurysm to the superior mesenteric artery, IVR embolization for the IPDA aneurysm was performed on postoperative day 8, and he was transferred to a rehabilitation hospital on postoperative day 57. The pathological result was invasive intraductal papillary mucinous carcinoma(IPMC). The patient has been an outpatient with no recurrence 12 months postoperatively.

Elevated expression of RAB3B plays important roles in chemoresistance and metastatic potential of hepatoma cells.

BACKGROUND: Cancer stem cells (CSCs) are thought to play important roles in carcinogenesis, recurrence, metastasis, and therapy-resistance. We have successfully induced cancer stem-like sphere cells (CSLCs) which possess enhanced chemoresistance and metastatic potential. To enable the development of targeted therapy against CSLCs, we identified a gene responsible for this phenotype in CSLC. METHODS: Human hepatoma cell line SK-HEP-1 was used for CSLC induction with a unique sphere inducing medium, and HuH-7 cells were used as non-sphere forming cells in the same condition. RNA-sequencing was performed followed by validation with quantitative RT-PCR and western blotting. Knockdown experiments were done by using CRISPR-Cas9 genome-editing, and the rescue experiments were performed using the expressing plasmid vector. Chemoresistance and liver metastasis of the cells, was studied following the splenic injection of cells to severely immune deficient mice and evaluated using the MTS assay. Quantification of exosomes in the medium was done using ELISA. RESULTS: RAB3B was identified as an up-regulated gene in both CSLCs and prognostically poor hepatocellular carcinoma (HCC) by RNA-sequencing. RAB3B-KD cells showed altered CSLC phenotypes such as sphere formation, chemoresistance, and metastatic potentials, and those were rescued by RAB3B complementation. Increased exosome secretion was observed in CSLCs, and it was not observed in the RAB3B-KD cells. In addition, the RAB3B expression correlated with the expression of ABCG2, APOE, LEPR, LXN, and TSPAN13. CONCLUSION: The up regulation of RAB3B may play an important role in the chemoresistance and metastatic potential of CSLCs.

CD4 and FOXP3 as predictive markers for the recurrence of T3/T4a stage II colorectal cancer: applying a novel discrete Bayes decision rule.

BACKGROUND: We recently reported the relapse-free survival (RFS) significance of the combination of CD4+ and forkhead box P3+ (FOXP3) T-cell densities identified by immunohistochemistry in patients with stage I, II, and III colorectal cancer (CRC) who underwent curative resections. This study was designed to determine the optimal combination of markers that predict recurrence in patients with T factors of T3/T4a stage II CRC by applying a novel Bayes decision rule. METHODS: Using 137 cancer tissue specimens from T3/T4a stage II patients, 12 clinicopathologic and immune factors were analysed as predictive candidates for recurrence. RESULTS: Our study showed that the combination of low CD4+ and low FOXP3+ T-cell densities resulted in extremely poor RFS. CONCLUSIONS: Adjuvant chemotherapy may be considered for patients with a combination of low CD4+ and low FOXP3+ T-cell densities. The discovery of this new prognostic indicator is important for the appropriate management of patients undergoing curative resection for T3/T4a stage II CRC.

[A Case in Which FOLFOXIRI Was Useful as Preoperative Chemotherapy for Locally Advanced Rectal Cancer with Difficulty in Securing CRM].

The patient is a 65-year-old woman. Colonoscopy performed for close examination of constipation and lower abdominal pain revealed a circumferential type 3 lesion in the rectum Ra. A CT scan showed invasion of the primary lesion into the extramural and sacral front and multiple metastases in the mesorectal lymph nodes but no distant metastasis. Staging laparoscopy was performed. As the mesorectum around the primary lesion was tightly adherent, it was difficult to R0 resection; hence, only construction of colostomy was performed. We have introduced chemotherapy(FOLFOXIRI plus bevacizumab therapy), and 4 courses were administered. Post-treatment CT scan showed that the peri-invasiveness of the primary tumor had disappeared and the enlarged lymph nodes had shrunk. Furthermore, SUVmax of PET-CT for main lesion was decreased, dramatically. On day 109 after the initial surgery, laparoscopic low anterior resection was performed. Although the left hypogastric nerve was resected, other areas could be dissected and R0 resection could be performed. FOLFOXIRI therapy has shown good early-tumor shrinkage and depth of response and may be useful for patients with locally advanced rectal cancer who have difficulty securing circumferential resection margin(CRM).

[Tumor Immunogenicity and Immune Checkpoint Inhibitors].

Cancer immunotherapy including immune checkpoint inhibitors(ICIs)have established itself as the fourth cancer therapy. However, the response rate of ICIs is still only about 20%, and tumors resistant to ICIs are often so-called"cold-tumor"with low tumor immunogenicity. Therefore, research and development is being conducted worldwide on how to convert cold- tumors into hot-tumors with high immunogenicity. In this paper, we review the relationship between tumor immunogenicity and ICI, as well as therapeutic methods to enhance tumor immunogenicity, and introduce our research about novel cancer peptide vaccination therapy.