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Colorectal cancer (CRC) is one of the most common cancers and the second most deadly cancer across the globe. Colorectal cancer stem cells (CCSCs) fuel CRC growth, metastasis, relapse, and chemoresistance. A complete understanding of the modulatory mechanisms of CCSC biology is essential for developing efficacious CRC treatment. In the current study, we characterized the expression and function of GTP binding protein 2 (GTPBP2) in a chemical-induced mouse CRC model. We found that GTPBP2 was expressed at a higher level in CD133+CD44+ CCSCs compared with other CRC cells. Using a lentivirus-based Cas9/sgRNA system, GTPBP2 expression was ablated in CRC cells in vitro. GTPBP2 deficiency caused the following effects on CCSCs: 1) Significantly accelerating proliferation and increasing the proportions of cells at G1, S, and G2/M phase; 2) Impairing resistance to 5-Fluorouracil; 3) Weakening self-renewal but not impacting cell migration. In addition, GTPBP2 deficiency remarkably decreased β-catenin expression while increasing β-catenin phosphorylation in CCSCs. These effects of GTPBP2 were present in CCSCs but not in other CRC cell populations. The Wnt agonist SKL2001 completely abolished these changes in GTPBP2-deficient CCSCs. When GTPBP2-deficient CCSCs were implanted in nude mice, they exhibited consistent changes compared with GTPBP2-expressing CCSCs. Collectively, this study indicates that GTPBP2 positively modulates Wnt signaling to reinforce the quiescence, self-renewal, and chemoresistance of mouse CCSCs. Therefore, we disclose a novel mechanism underlying CCSC biology and GTPBP2 could be a therapeutic target in future CRC treatment.

Natural killer (NK) cells constitute an active and potent anti-tumor effector population against multiple malignancies. NK cells exploit tumoricidal machinery to restrain colorectal carcinoma (CRC) expansion and invasion. Nonetheless, it is becoming increasingly evident that functional exhaustion considerably compromises the potency of NK cells in patients with CRC. To elucidate the factors that impair NK cell function in the context of CRC, we determined the role of zinc finger protein 335 (ZFP335) in modulating NK cell activity in mouse CRC induced by azoxymethane and dextran sulfate sodium. ZFP335 was profoundly decreased in NK cells in mesenteric lymph nodes of CRC-bearing mice. ZFP335 was especially diminished in NK cells that were both phenotypically and functionally exhausted. Besides, effective ZFP335 knockdown markedly undermined NK cell proliferation, tumoricidal protein production, degranulation, and cytotoxic efficacy on malignant cells, strongly suggesting that ZFP335 reinforces NK cell function. Importantly, ZFP335 knockdown lowered the expression of Janus kinase 1 (JAK1) and Janus kinase 3 (JAK3), both of which play crucial roles in NK cell homeostasis and activation. Collectively, ZFP335 down-regulation is essential for NK cell exhaustion in mesenteric lymph nodes of mice with CRC. We discovered a new ZFP335-JAK1/3 signaling pathway that modulates NK cell exhaustion.

Background Previous studies confirmed that most neoantigens predicted by algorithms do not work in clinical practice, and experimental validations remain indispensable for confirming immunogenic neoantigens. In this study, we identified the potential neoantigens with tetramer staining, and established the Co-HA system, a single-plasmid system coexpressing patient human leukocyte antigen (HLA) and antigen, to detect the immunogenicity of neoantigens and verify new dominant hepatocellular carcinoma (HCC) neoantigens.Methods First, we enrolled 14 patients with HCC for next-generation sequencing for variation calling and predicting potential neoantigens. Then, the Co-HA system was established. To test the feasibility of the system, we constructed target cells coexpressing HLA-A*11:01 and the reported KRAS G12D neoantigen as well as specific T-cell receptor (TCR)-T cells. The specific cytotoxicity generated by this neoantigen was shown using the Co-HA system. Moreover, potential HCC-dominant neoantigens were screened out by tetramer staining and validated by the Co-HA system using methods including flow cytometry, enzyme-linked immunospot assay and ELISA. Finally, antitumor test in mouse mode and TCR sequencing were performed to further evaluate the dominant neoantigen.Results First, 2875 somatic mutations in 14 patients with HCC were identified. The main base substitutions were C>T/G>A transitions, and the main mutational signatures were 4, 1 and 16. The high-frequency mutated genes included HMCN1, TTN and TP53. Then, 541 potential neoantigens were predicted. Importantly, 19 of the 23 potential neoantigens in tumor tissues also existed in portal vein tumor thrombi. Moreover, 37 predicted neoantigens restricted by HLA-A*11:01, HLA-A*24:02 or HLA-A*02:01 were performed by tetramer staining to screen out potential HCC-dominant neoantigens. HLA-A*24:02-restricted epitope 5'-FYAFSCYYDL-3' and HLA-A*02:01-restricted epitope 5'-WVWCMSPTI-3' demonstrated strong immunogenicity in HCC, as verified by the Co-HA system. Finally, the antitumor efficacy of 5'-FYAFSCYYDL-3'-specific T cells was verified in the B-NDG-B2mtm1Fcrntm1(mB2m) mouse and their specific TCRs were successfully identified.Conclusion We found the dominant neoantigens with high immunogenicity in HCC, which were verified with the Co-HA system.

Abstract Background Obstructive jaundice caused by primary duodenal lymphoma is a rare disease. Case presentation We reported a 59-year-old man who underwent endoscopic ultrasonography for obstructive jaundice and found a duodenal papilla tumor. Light microscopy revealed a non-Hodgkin's lymphoma. Immunohistochemical staining showed that the tumor was aggressive B-cell lymphoma. We carried out molecular targeted therapy combined with CHOP regimen chemotherapy. Conclusion Surgery plays an important role in resolving obstructive jaundice when accurate histological diagnosis cannot be made. After diagnosis, chemotherapy should play a central role in treatment.

Abstract Background Cocoon abdomen is a relatively rare abdominal disease characterized by the total or partial encasement of the small intestinal by a dense fibro-collagenous membrane. Case presentation We reported an unusual case of idiopathic cocoon abdomen with congenital colon malrotation. Laparotomy and sac release were performed on the patient. The patient was no recurrence 6 months after operation. A literature review was also performed. Conclusion Preoperative diagnosis of abdominal cocoon is difficult. A careful history, physical examination and appropriate radiology may be helpful in making a definitive diagnosis. If conservative treatment can’t relieve symptoms effectively, surgery is currently considered to be important in the management of this disease.

Abstract Background Identification of novel MDM2 or p53 binding proteins may reveal undefined oncogenes, tumor suppressors, signaling pathways and possible treatment targets. Methods By means of immunoprecipitation and Mass Spectrometry analysis, we aimed to identify novel regulators of the MDM2-p53 pathway. We further clarified the impact of MYL6B on the p53 protein level and on the process of apoptosis. We also investigated the role of MYL6B in hepatocellular carcinoma by clone formation assay and by determining the correlation between its expression and prognosis of HCC patients. Results We identified a novel MDM2 and p53 binding protein, MYL6B. It is a myosin light chain that could bind myosin II heavy chains to form non-muscle myosin II holoenzymes (NMII). We found that MYL6B could facilitate the binding of MDM2 to p53, which consequently promotes the ubiquitination and degradation of p53 protein. We further proved that MYL6B exerts the suppression effect on p53 as part of NMII holoenzymes because inhibiting the ATPase activity of myosin II heavy chain largely blocked this effect. We also discovered that MYL6B is overexpressed in HCC tissues and linked to the bad prognosis of HCC patients. Knocking out of MYL6B dramatically suppressed the clonogenic ability and increased the apoptosis level of HCC cell lines. Conclusions To summary, our results demonstrate that MYL6B is a putative tumor driver gene in HCC which could promote the degradation of p53 by enhancing its’ MDM2-mediated ubiquitination.

Currently, there is no effective vaccine to prevent hepatitis C virus (HCV) infection, partly due to our insufficient understanding of the virus glycoprotein immunology. Most neutralizing antibodies (nAbs) were identified using glycoprotein immunogens, such as recombinant E1E2, HCV pseudoparticles or cell culture derived HCV. However, the fact that in the HCV acute infection phase, only a small proportion of patients are self-resolved accompanied with the emergence of nAbs, indicates the limited immunogenicity of glycoprotein itself to induce effective antibodies against a highly evolved virus. Secondly, in previous reports, the immunogen sequence was mostly the genotype of the 1a H77 strain. Rarely, other genotypes/subtypes have been studied, although theoretically one genotype/subtype immunogen is able to induce cross-genotype neutralizing antibodies. To overcome these drawbacks and find potential novel neutralizing epitopes, 57 overlapping peptides encompassing the full-length glycoprotein E1E2 of subtype 1b were synthesized to immunize BALB/c mice, and the neutralizing reactive of the induced antisera against HCVpp genotypes 1-6 was determined. We defined a domain comprising amino acids (aa) 192-221, 232-251, 262-281 and 292-331 of E1, and 421-543, 564-583, 594-618 and 634-673 of E2, as the neutralizing regions of HCV glycoprotein. Peptides PUHI26 (aa 444-463) and PUHI45 (aa 604-618)-induced antisera displayed the most potent broad neutralizing reactive. Two monoclonal antibodies recognizing the PUHI26 and PUHI45 epitopes efficiently precluded genotype 2 viral (HCVcc JFH and J6 strains) infection, but they did not neutralize other genotypes. Our study mapped a neutralizing epitope region of HCV glycoprotein using a novel immunization strategy, and identified two monoclonal antibodies effective in preventing genotype 2 virus infection.

It has been reported that monoclonal antibodies (MAbs) to the E1E2 glycoproteins may have the potential to prevent hepatitis C virus (HCV) infection. The protective epitopes targeted by these MAbs have been mapped to the regions encompassing amino acids 313-327 and 432-443. In this study, we synthesized these two peptides and tested the reactivity of serum samples from 336 patients, 210 of which were from Chronic Hepatitis C (CHC) patients infected with diverse HCV genotypes. The remaining 126 samples were isolated from patients who had spontaneously cleared HCV infection. In the chronic HCV-infected group (CHC group), the prevalence of human serum antibodies reactive to epitopes 313-327 and 432-443 was 24.29% (51 of 210) and 4.76% (10 of 210), respectively. In the spontaneous clearance group (SC group), the prevalence was 0.79% (1 of 126) and 12.70% (16 of 126), respectively. The positive serum samples that contained antibodies reactive to epitope 313-327 neutralized HCV pseudoparticles (HCVpp) bearing the envelope glycoproteins of genotypes 1a or 1b and/or 4, but genotypes 2a, 3a, 5 and 6 were not neutralized. The neutralizing activity of these serum samples could not be inhibited by peptide 313-327. Six samples (SC17, SC38, SC86, SC92, CHC75 and CHC198) containing antibodies reactive to epitope 432-443 had cross-genotype neutralizing activities. The neutralizing activity of SC38, SC86, SC92 and CHC75 was partially inhibited by peptide 432-443. However, the neutralizing activity of sample SC17 for genotype 4HCVpp and sample CHC198 for genotype 1b HCVpp were not inhibited by the peptide. This study identifies the neutralizing ability of endogenous anti-HCV antibodies and warrants the exploration of antibodies reactive to epitope 432-443 as sources for future antibody therapies.

Recurrence plots and recurrence quantification were used to analyze pressure fluctuation signals in a dense gas-solid fluidized bed. Parameters including determinism (QDET), average diagonal line length (QL), and laminarity(QLAM) were determined from the recurrence plot. Comparative analysis of the flow images and parameters was performed. The bubbles become larger, and the chaotic characteristic in the fluidized bed strengthens with increasing gas velocity. The biomass particles are preferentially blown to the upper layer and mixed with quartz sand at high gas speed. Large bubbles in the fluidized the bed can be easily broken by biomass particles with increasing biomass concentration. The presence and movement of large cylindrical biomass lead to decreased bubble size, uniform energy, and reduced QDET, QL and QLAM. The minimum fluidization velocity of the mixed flow of quartz sand and biomass is 0.5m/s. The pressure drop increases with increasing bed height and is not related to biomass concentration. [ABSTRACT FROM AUTHOR]

Background: PD-L1 expression on neutrophils contributes to the impaired immune response in infectious disease, but the detailed role of PD-L1 expression on neutrophils in HCC remains unclear. Methods: We investigated the phenotype and morphology of neutrophils infiltrated in tumour tissues from both patients with HCC and hepatoma-bearing mice. Results: We found that neutrophils dominantly infiltrated in the peritumoural region. The neutrophil-to-T cell ratio (NLR) was higher in peritumoural tissue than that in the intratumoural tissue and was negatively correlated with the overall survival of patients with HCC. Infiltrating neutrophils displayed a phenotype of higher frequency of programmed cell death ligand 1 (PD-L1) positive neutrophils. The ratio of PD-L1+ neutrophils-to-PD-1+ T cells was higher in peritumoural tissue and better predicted the disease-free survival of patients with HCC. We further confirmed a higher frequency of PD-L1+ neutrophils and PD-1+ T cells in hepatoma-bearing mice. Functionally, the PD-L1+ neutrophils from patients with HCC effectively suppressed the proliferation and activation of T cells, which could be partially reversed by the blockade of PD-L1. Conclusions: Our results indicate that the tumour microenvironment induces impaired antitumour immunity via the modulation of PD-L1 expression on tumour infiltrating neutrophils. [ABSTRACT FROM AUTHOR]

Background: Previous evidence has shown that the FOXP3 gene was involved in the pathogenesis of several tumors; however, the correlation between single nucleotide polymorphisms (SNPs) in the FOXP3 gene and the susceptibility to hepatitis B-related hepatocellular carcinoma (HCC) remains unclear. Methods: We analyzed two SNPs in the FOXP3 gene, rs2280883 and rs3761549, in 392 patients with HCC, 344 patients with chronic hepatitis B (CHB) and 372 matched healthy controls. Genotyping was performed by MALDI-TOF Mass Spectrometry for all donors. Results: Compared to healthy controls, HCC patients had higher frequencies of the TT genotype (79.6%) at rs2280883 and the CC genotype (77.6%) at rs3761549 of the FOXP3 gene; CHB patients also had higher frequencies of the TT genotype (74.1%) at rs2280883 and the CC genotype (74.6%) at rs3761549. There were no significant differences in the distribution of FOXP3 genotypes between CHB donors and HCC donors. The TT genotype at rs2280883 was more frequent in patients with HCC than healthy donors (P = 0.01), but no significant difference was observed in this genotype between CHB and healthy donors (P = 0.479). C allele frequency at rs3761549 was higher in HCC patients than healthy donors (P = 0.03), but distribution of this allele was not significantly different between CHB patients and healthy donors (P = 0.11). Stratified analysis showed that the CC genotype at rs3761549 was significantly associated with a high incidence of portal vein tumor thrombus (P = 0.02) and that the TT/CT genotype at rs3761549 was significantly associated with an increased rate of tumor recurrence in HCC patients (P = 0.001). Conclusions: Our results suggested that the FOXP3 gene polymorphisms at rs2280883 and rs3761549 may be associated with hepatitis B-related HCC. At rs3761549, the CC genotype and the TT/CT genotype were associated with a high incidence of portal vein tumor thrombus and tumor recurrence, respectively. [ABSTRACT FROM AUTHOR]