Clinicopathological study on pIgR expression and tumor progression in advanced colorectal cancer

This study is aimed at investigating the relationship between the polymeric immunoglobulin receptor （pIgR） expression and clinicopathological factors in advanced colorectal cancer （CRC） patients. The study involved 47 advanced CRC patients who were surgically resected and underwent KRAS gene test. The pIgR expression was analyzed by immunohistochemistry, and the patients were classified into high and low （pIgR-H and pIgR-L, respectively） groups based on the staining intensity and range. A total of 13 cases was classified under the pIgR-H group, and the remaining 34 were classified under the pIgR-L group. Results suggest no significant differences in most clinicopathological factors between the pIgR-H and pIgR-L groups, although the pIgR-L group had a significantly higher frequency of venous invasion than the pIgR-H group, whereas the frequency of KRAS gene mutation was significantly higher in the pIgR-H group than that in the pIgR-L group. The findings in this study showed little significant correlation between the pIgR expression and clinicopathological factors in advanced CRC patients. Further research on the biological behavior of pIgR as a drug treatment option for KRAS-mutated advanced CRCs is also warranted

CCR6+ MCAM+ Th17 Cell Numbers Increase in Patients with Psoriasis and Correlate with Disease Severity

Psoriasis is a chronic immune-mediated disease in which the interleukin (IL)-23/IL-17 axis plays a key role in the inflammatory cascade. We recently reported that co-expression of CCR6 and melanoma cell adhesion molecule (MCAM) in effector memory CD4 T cells (TEM) of peripheral blood might be a useful marker for T helper (Th) 17 cells. In this study, we monitored changes in TEM expressing CCR6 and MCAM using the Psoriasis Area and Severity Index (PASI) score during anti-tumor necrosis factor (TNF) therapy. We also studied CCR6+ MCAM+ Th17 cells histologically in skin biopsy samples from psoriasis patients. In psoriasis patients treated with anti-TNF therapy, the PASI score and the percentage of CCR6+ MCAM+ TEM cells in the blood changed almost in parallel. In immunohistochemical analyses, the proportions of IL-17+ T cells and MCAM+ T cells in the lesional skin of severely psoriatic patients were significantly higher than in mildly psoriatic patients (P<0.05), and the number of IL17+ T cells correlated with the PASI score (r=0.400, P<0.05). Taken together, these results indicate that CCR6+ MCAM+ Th17 cells in peripheral blood and lesional skin might play an important role in the pathology of psoriasis

Analysis of the MYD88 L265P mutation in IgM monoclonal gammopathy by semi-nested polymerase chain reaction-based restriction fragment length polymorphism method

MYD88 L265P mutation causes constitutive activation of NF-κB and possible driver mutation in B-cell lymphoid malignancies. It is frequently detected in Waldenstrom’s macroglobulinemia （WM） （50％-100％）, and its detection is important in diagnostic and therapeutic targets of this syndrome. Standard detection method of MYD88 L265P mutation in clinical practice has yet to be established. We developed semi-nested PCR-based restriction fragment length polymorphism （snPCR-RFLP） to detect the mutation. The snPCR-RFLP method is a modification of the PCR-RFLP method, which uses the restriction enzyme BsiEI that recognizes CGACT/CG, intending to increase detection sensitivity by amplification of mutated allele in the DNA sample using semi-nested PCR before enzyme digestion. The detection sensitivity of snPCR-RFLP was estimated as 0.1％, by detecting mutated allele in wild-type allele in the cloned plasmid DNA, which is comparable with allele-specific （AS） PCR method widely used as sensitive detection method. By analyzing 40 cases with IgM monoclonal gammopathy, snPCR-RFLP detected 29/40 （70％） of all cases, 22/31 （70.9％） of WM, and 6/9 （66.6%） of IgM-type monoclonal gammopathy with undetermined significance （IgMMGUS）, including five cases （three cases of WM and two cases of IgMMGUS） in which the mutation was detected only by snPCR-RFLP but not by Sanger sequencing method. Regarding DNA sample status, particularly five cases, a case was extracted from formalin-fixed paraffin-embedded tissue and four cases were extracted from cells by Ficoll-Hypaque density gradient. In correlation with clinical features, the MYD88 mutation detected by snPCR-RFLP method was associated with the adverse prognostic index （WMIPSS） of WM using patient age, hemoglobin （Hb） level, platelet count, β2MG level, and serum IgM level （p＝0.055）. The snPCR-RFLP method is a clinically useful MYD88 mutation detection method that can be performed in general laboratories

Mast Cell Infiltration is Associated with Myelofibrosis and Angiogenesis in Myelodysplastic Syndromes

Myelodysplastic syndromes are a heterogeneous group of clonal hematopoietic stem cell disorders characterized by persistent peripheral cytopenia with morphological and functional abnormalities of hematopoietic cells. Mast cells infiltrate into or around tumor tissues and play a role in remodeling of the stromal microenvironment, contributing to tumor progression. Increased mast cell numbers are associated with fibrosis, angiogenesis and a poor prognosis in human carcinomas. The aim of this study was to determine whether mast cell infiltration contributes to myelofibrosis or angiogenesis in myelodysplastic syndromes. We evaluated the correlation between mast cell density and the extent of myelofibrosis and angiogenesis in myelodysplastic syndromes. Fifty bone marrow biopsies taken from patients with a diagnosis of myelodysplastic syndromes were examined. Grading of myelofibrosis was evaluated by silver impregnation staining. Mast cell density and microvessel density were evaluated by immunohistochemistry. Human mast cells have been divided into two phenotypes. We designated a tryptase-positive mast cell as MCT and a chymase-positive mast cell as MCTC. Microvessels were identified by CD34-positive endothelial cells. Microvessel density and the extent of myelofibrosis were significantly greater in patients with high MCT and MCTC density compared to those with low MC density. Based on this, we suggest that the presence of high mast cell numbers is associated with myelofibrosis and angiogenesis in myelodysplastic syndromes

Magnifying Colonoscopy Findings for Differential Diagnosis of Sessile Serrated Adenoma/Polyps and Hyperplastic Polyps

Sessile serrated adenoma/polyps (SSA/Ps) are thought to be precursors of colorectal cancers. However, current endoscopic techniques for differentiating SSA/Ps from conventional hyperplastic polyps (HPs) have low diagnostic accuracy. The aim of the present study was to assess the ability of mucosal crypt patterns to distinguish SSA/Ps from HPs. We examined 140 lesions from 93 patients that had been diagnosed histologically as SSA/Ps or HPs at the Showa University Hospital between June 2010 and May 2012. Three experienced colonoscopists reviewed the endoscopic findings of magnifying colonoscopy. Type II open-shape (Type II-O) pit patterns and varicose microvascular vessels (VMVs) were identified according to previously proposed definitions. Although 140 lesions were initially identified for the study, 27 lesions were excluded from analysis because of insufficient endoscopic findings. Thus, endoscopic findings from a total of 113 lesions (68 SSA/Ps and 45 HPs) were evaluated. Of 113 serrated polyps, 51 lesions (44 SSA/Ps and 7 HPs; P<0.01) had Type II-O pit patterns. The inter- and intra-observer agreement for these patterns among three colonoscopists was κ=0.61 (range 0.57–0.65) and κ=0.68 (range 0.52–0.94), respectively. The positive predictive value (PPV), negative predictive value (NPV), sensitivity, and specificity of Type II-O pit patterns for differentiating between SSA/P and HP were 86%, 61%, 65%, and 84%, respectively. In contrast, the PPV, NPV, sensitivity, and specificity of VMVs were 68%, 43%, 37%, and 73%, respectively. The results indicate that Type II-O mucosal crypt patterns may be useful for the differential diagnosis of SSAPs and HPs

Novel quantitative immunohistochemical analysis for evaluating PD-L1 expression with phosphor-integrated dots for predicting the efficacy of patients with cancer treated with immune checkpoint inhibitors

IntroductionProgrammed cell death ligand 1 (PD-L1) expression in tumor tissues is measured as a predictor of the therapeutic efficacy of immune checkpoint inhibitors (ICIs) in many cancer types. PD-L1 expression is evaluated by immunohistochemical staining using 3,3´-diaminobenzidine (DAB) chronogenesis (IHC-DAB); however, quantitative and reproducibility issues remain. We focused on a highly sensitive quantitative immunohistochemical method using phosphor-integrated dots (PIDs), which are fluorescent nanoparticles, and evaluated PD-L1 expression between the PID method and conventional DAB method.MethodsIn total, 155 patients with metastatic or recurrent cancer treated with ICIs were enrolled from four university hospitals. Tumor tissue specimens collected before treatment were subjected to immunohistochemical staining with both the PID and conventional DAB methods to evaluate PD-L1 protein expression.ResultsPD-L1 expression assessed using the PID and DAB methods was positively correlated. We quantified PD-L1 expression using the PID method and calculated PD-L1 PID scores. The PID score was significantly higher in the responder group than in the non-responder group. Survival analysis demonstrated that PD-L1 expression evaluated using the IHC-DAB method was not associated with progression-free survival (PFS) or overall survival (OS). Yet, PFS and OS were strikingly prolonged in the high PD-L1 PID score group.ConclusionQuantification of PD-L1 expression as a PID score was more effective in predicting the treatment efficacy and prognosis of patients with cancer treated with ICIs. The quantitative evaluation of PD-L1 expression using the PID method is a novel strategy for protein detection. It is highly significant that the PID method was able to identify a group of patients with a favorable prognosis who could not be identified by the conventional DAB method

Plasmid analysis of clinically isolated Enterobacter cloacae in Showa University Hospital

We have reported the possibility of an outbreak of a plasmid-borne carbapenemase-producing Enterobacteriaceae at Showa University Hospital using conjugal transfer experiments; however, we could not perform plasmid profiling and fingerprinting to identify the plasmid responsible for the outbreak in clinical isolates. Therefore, to distinguish whether the appearance of metallo-β-lactamase IMP-11 （blaIMP-11）-producing Enterobacter cloacae （E. cloacae） was due to the same plasmid, we established a plasmid testing system involving plasmid isolation, typing, profiling, and fingerprinting, as well as DNA sequencing analysis of genes surrounding the carbapenemase-encoding gene. Plasmid fingerprinting is an essential tool for identifying plasmids when next-generation sequencing methods cannot be employed. Of note, an important step in fingerprinting is plasmid isolation, which is difficult when large plasmids are involved. In addition, plasmid profiling using S1 nuclease pulse-field gel electrophoresis （PFGE） Southern blotting is an important tool for profiling the size and number of plasmids in bacteria. In this study, we successfully isolated an approximately 90-kb IncL/M plasmid by employing our plasmid analysis system. Importantly, as different blaIMP-11-producing E. cloacae isolates carried the same type of plasmid, with similar size and fingerprinting pattern, we suggest that the isolated IncL/M plasmid is the one present in this strain

Atypical Mucosa-Associated Lymphoid Tissue Lymphoma in the Transverse Colon Associated with Macroglobulinemia （マクログロブリン血症を伴った横行結腸の非定型粘膜関連リンパ組織リンパ腫）

AuthorWe herein present a quite atypical case of primary gastrointestinal mucosa-associated lymphoid tissue (MALT) lymphoma in the transverse colon. Computed tomography and endoscopic ultrasonography revealed diffuse thickening of the wall, and colonoscopy showed a white-colored mucosa with reduced superficial vessels in the entire transverse colon. The lesion was diagnosed as MALT lymphoma by pathological examination for biopsied specimen. Secondary macroglobulinemia of IgM-κ type was also found in the present case. After chemotherapy and radiation, the lesions in the transverse colon have improved and the patient has been in good condition without any evidence of recurrence for more than 1 year. 横行結腸における原発性消化管粘膜関連リンパ組織(MALT)リンパ腫のきわめて特異な54歳日本人女性症例について検討した。CTおよび超音波内視鏡で結腸壁のびまん性肥厚が認められ、結腸内視鏡で横行結腸全体に表面血管の減少を伴う白色粘膜が認められた。生検標本の病理検査にて、病変はMALTリンパ腫と診断された。IgM-κ型の続発性マクログロブリン血症も明らかになった。化学療法および放射線療法を施行したところ、横行結腸の病変は改善し、患者の状態は1年以上にわたり良好であった

Right colon cancer presenting as hemorrhagic shock

A 67-year-old man visited our hospital with a history of continuous hematochezia leading to hemorrhagic shock. An abdominal computed tomography scan revealed a large mass in the ascending colon invading the duodenum and pancreatic head as well as extravasation of blood from the gastroduodenal artery (GDA) into the colon. Colonoscopy revealed an irregular ulcerative lesion and stenosis in the ascending colon. Therefore, right hemicolectomy combined with pylorus-preserving pancreaticoduodenectomy was performed. Histologically, the tumor was classified as a moderately differentiated adenocarcinoma. Moreover, cancer cells were mainly located in the colon but had also invaded the duodenum and pancreas and involved the GDA. Immunohistochemically, the tumor cells were positive for cytokeratin (CK)20 and carcinoembryonic antigen (CEA) but not for CK7 and carbohydrate antigen (CA)19-9. The patient died 23 d after the surgery because he had another episode of arterial bleeding from the anastomosis site. Although En bloc resection of the tumor with pancreaticoduodenectomy and colectomy performed for locally advanced colon cancer can ensure long-term survival, patients undergoing these procedures should be carefully monitored, particularly when the tumor involves the main artery