CXCL8 induces M2 macrophage polarization and inhibits CD8+ T cell infiltration to generate an immunosuppressive microenvironment in colorectal cancer.

The poor prognosis of immunotherapy in patients with colorectal cancer (CRC) necessitates a comprehensive understanding of the immunosuppressive mechanisms within tumor microenvironment (TME). Undoubtedly, the anti-tumor immune cells play an indispensable role in immune tolerance. Therefore, it is imperative to investigate novel immune-related factors that have the capacity to enhance anti-tumor immunity. Here, we employed bioinformatic analysis using R and Cytoscape to identify the hub gene chemokine (C-X-C motif) ligand 8 (CXCL8), which is overexpressed in CRC, in the malignant progression of CRC. However, its specific role of CXCL8 in CRC immunity remains to be elucidated. For this purpose, we evaluated how tumor-derived CXCL8 promotes M2 macrophage infiltration by in vivo and in vitro, which can be triggered by IL-1ß within TME. Mechanistically, CXCL8-induced polarization of M2 macrophages depends on the activation of the STAT3 signaling. Finally, immunohistochemistry and multiplexed immunohistochemistry analysis identified that CXCL8 not only enhances PD-L1+ M2 macrophage infiltration but also attenuates the recruitment of PD-1+ CD8+ T cells in murine CRC models. Together, these findings emphasize the critical role for CXCL8 in promoting M2 macrophage polarization and inhibiting CD8+ T cell infiltration, thereby links CXCL8 to the emergency of immunosuppressive microenvironment facilitating tumor evasion. Overall, these findings may provide novel strategy for CRC immunotherapy.

miR-148a-3p silences the CANX/MHC-I pathway and impairs CD8+ T cell-mediated immune attack in colorectal cancer.

Nonresponse, or acquired resistance to immune checkpoint inhibitors in colorectal cancer (CRC) highlight the importance of finding potential tolerance mechanisms. Low expression of major histocompatibility complex, class I (MHC-I) on the cell surface of the tumor is one of the main mechanisms of tumor escape from T-cell recognition and destruction. In this study, we demonstrated that a high level of calnexin (CANX) in the tumors is positively correlated with the overall survival in colorectal cancer patients. CANX is a chaperone protein involved in the folding and assembly of MHC-I molecules. Using miRNA target prediction databases and luciferase assays, we identified miR-148a-3p as a potential regulator of CANX. Inhibition of miR-148a-3p restores surface levels of MHC-I and significantly enhanced the effects of CD8+ T-cell-mediated immune attack in vitro and in vivo by promoting CANX expression. These results reveal that miR-148a-3p can function as a tumor promotor in CRC by targeting the CANX/MHC-I axis, which provides a rationale for immunotherapy through targeting the miR-148a-3p/CANX/MHC-I pathway in patients with CRC.

A combinatorial strategy for overcoming primary and acquired resistance of MEK inhibition in colorectal cancer.

Compared with traditional chemotherapeutic drugs, targeted therapeutic medicine has the advantages of high efficacy and less toxic side effects. However, in clinical practice for treatment of colorectal cancer, the primary and acquired resistance of these medicines limits their effectiveness in targeted therapy, therefore impedes the development of precision medicine and personalized therapy. Currently, there are limited number of drugs for targeted therapy of colorectal cancer, mainly monoclonal antibodies against EGFR or VEGFR inhibitors. Trametinib, a MEK inhibitor, has been applied in melanoma patient successfully, but not been used in clinical treatment of colorectal cancer because of its drug resistance. To identify the resistance mechanism of colorectal cancer cells to trametinib and find useful chemical combination to overcome the resistance, we screened primary and acquired cell line first and then tested multiple synergistic drug combinations by using the Chou-Talalay method. We obtained the primary resistant cell lines SW480, CW-2 and the acquired drug-resistant cell line RKO-R as well as a synergistic combination of trametinib and GSK2126458. This combination inhibits the colony formation of colorectal cancer cells and the growth of xenograft tumors in nude mice. Mechanistic analysis showed that trametinib can activate the alternative PI3K-AKT signaling pathway while inhibiting the MAPK pathway, which may be one of the molecular mechanisms of primary and acquired trametinib tolerance in colorectal cancer cells. Importantly, this bypass activation can be blocked by GSK2126458. These results suggest that a combination of trametinib and GSK2126458 is an effective approach for treating colorectal cancer resistance to trametinib.

Macroinvertebrate communities and the relationships with biotic factors in river-connected lakes in the lower reaches of Yangtze River, China.

The relationships of macroinvertebrate communities with abiotic factors in lake and river system were well documented, but their relationships with biotic factors were few explored. The macroinvertebrate communities in two river-disconnected lakes (Poyang Lake and Shijiu Lake) and the rivers connected to Shijiu Lake were investigated to reveal the differences in communities and explore the relationships with biotic factors. A total of 34 species were recorded in the three water bodies. Combined with the previous study results, the dominant species in Poyang Lake is almost unchanged since 1997. Mollusks were dominated in abundance in Poyang Lake and the rivers connected to Shijiu Lake, while oligochaetes dominated the communities in Shijiu Lake. The alpha diversity indices of macroinvertebrates in Poyang Lake and the rivers connected to Shijiu Lake were distinctly higher than that of Shijiu Lake, and the beta diversity index of Shijiu Lake was the highest, supporting the rules that alpha diversity of macroinvertebrates achieves a maximum at a moderate level of connectivity and beta diversity seems to be higher when the connectivity is weaker. The differences in communities were significant between the Poyang Lake and Shijiu Lake, while the differences in the Poyang Lake and the rivers connected to Shijiu Lake were not significant. According to the results of canonical correspondence analysis (CCA), protozoon densities and phytoplankton biomass affected the distribution of macroinvertebrates in Shijiu Lake. Species number of planktonic crustaceans influenced the distribution of macroinvertebrates in rivers connected to Shijiu Lake, while species number of rotifer and densities of phytoplankton distinctly impacted on the distribution of macroinvertebrates in Poyang Lake.

Real-world retrospective study of anti-PD-1 antibody in combination with chemotherapy as a neoadjuvant treatment strategy for locally advanced resectable esophageal squamous cell carcinoma.

Background: Neoadjuvant therapy has become a mainstay of treatment for locally advanced resectable esophageal cancer. The objective of this research was to investigate the effectiveness and safety of neoadjuvant immunotherapy combined with chemotherapy in treating surgically removable esophageal squamous cell carcinoma (ESCC). Methods: From January 1, 2016 to April 1, 2023, we conducted a retrospective analysis of patients diagnosed with resectable esophageal cancer who underwent neoadjuvant immunotherapy combined with chemotherapy at The First Affiliated Hospital of Nanchang University. The primary endpoints of this study were pathologic complete response (pCR), major pathologic response (MPR) and disease-free survival (DFS). The secondary endpoints of this study were overall survival (OS), objective response rate (ORR) and safety. Results: A total of 122 patients with ESCC receiving neoadjuvant immune-chemotherapy (nICT) were included. Fifty-four patients achieved partial response (PR) and two patients achieved complete response (CR), with an ORR of 45.9%. Of the 106 patients who underwent surgery, a total of 28 patients achieved pCR (26.4%) and a total of 37 patients achieved MPR (34.9%). Grade 3 or higher adverse events occurred in 26 patients (21.3%). The most common postoperative complication was pneumonitis (25.5%). Conclusions: Neoadjuvant immunotherapy combined with chemotherapy demonstrates satisfactory efficacy in the treatment of locally advanced ESCC, with manageable treatment-related adverse events and postoperative complications.

Clinical features and treatment outcomes of PD-1 inhibitor therapy in elderly patients (≥ 65 years) with advanced esophageal squamous cell carcinoma: a real-world study.

PURPOSE: This study aims to determine the clinical features and outcomes of PD-1 inhibitor therapy as the initial treatment in patients aged 65 years or older with locally advanced or metastatic esophageal squamous cell carcinoma (ESCC). MATERIALS AND METHODS: The retrospective study conducted a comprehensive analysis of elder patients diagnosed with locally advanced or metastatic ESCC who underwent combined immunochemotherapy in the first affiliated hospital of Nanchang University from January 2019 to January 2023. The main efficacy measures were the objective response rate (ORR) and progression-free survival (PFS). The secondary endpoints were disease control rate (DCR) and overall survival (OS). The evaluation of safety was based on the assessment of adverse events (AEs). RESULTS: A total of 88 patients were enrolled in the study. All patients received PD-1 inhibitors combined with chemotherapy including taxane and platinum as the first-line treatment. The median PFS was 6.2 months (95% CI: 5.1-7.3), and the median OS was 15.3 months (95% CI: 12.9-17.7). The ORR and DCR were 42.0% and 72.7%, correspondingly. 68 (77.3%) patients experienced treatment-related adverse events (TRAEs) of various degrees, with neutrophil count decreased (21, 23.9%) being the most frequent. TRAEs of grade 3 or 4 occurred in 13 (14.8%) patients. CONCLUSION: The study demonstrated that individuals older than 65 years with locally advanced or metastatic ESCC have a survival benefit from the first-line treatment of PD-1 inhibitors combined therapy, with a manageable safety profile.

Siglec-15 as multifunctional molecule involved in osteoclast differentiation, cancer immunity and microbial infection.

Siglec-15 is a highly conserved member of the Siglec family, expressed on osteoclasts, a subset of myeloid cells and some cancer cells. Except for regulating osteoclast differentiation, Siglec-15 engages in immunoregulation as an immune suppressor. Siglec-15 functions as an immunosuppressive molecule in tumor-associated macrophage-mediated T cell immunity in the tumor microenvironment (TME), which makes Siglec-15 to be an emerging and promising target for normalization cancer immunotherapy. Besides, Siglec-15 interacts with sialylated pathogens and modulates host immune response against microbial pathogens by altering cytokine production and/or phagocytosis, which further broadens the underlying pathophysiological roles of Siglec-15. The fact that N-glycosylation and sialylation of Siglec-15 play a pivotal role in Siglec-15 biological function indicates that targeting certain post-translational modification may be an effective strategy for targeting Siglec-15 therapy. In-depth exploring Siglec-15 biology function is crucial for better design of Siglec-15-based therapy according to different clinical indications.

A case report of two instances of colorectal hepatoid adenocarcinoma, accompanied by a comprehensive literature review.

OBJECTIVE: The study aimed to explore the clinical and pathological characteristics, survival outcomes, and prognostic factors of colorectal hepatoid adenocarcinoma. METHODS: We performed two cases of colorectal hepatoid adenocarcinoma treated at the Oncology Department of the First Affiliated Hospital of Nanchang University. We also reviewed literature up to the present and performed a retrospective study of colorectal hepatoid adenocarcinoma. RESULTS: Among the 39 patients included in this study, 28 had primary tumors in the colon, 9 in the rectum, and 2 in the rectosigmoid junction. The median age was 52 years (range 31-75 years); 28 patients (71.8%) were male. Out of the 32 patients for whom survival data were available, 24 patients succumbed to disease-related causes. The median overall survival of 32 patients was 8 months, with 1-year and 2-year overall survival rates of 31.0% and 16.0%, respectively. Univariate analysis revealed that depth of infiltration, presence of liver metastases, TNM stage, and the completeness of surgical resection were significantly associated with the overall survival period of colorectal hepatoid adenocarcinoma. CONCLUSION: Colorectal hepatoid adenocarcinoma exhibits a high degree of aggressiveness and poor prognosis. The major strategy for early-stage HAC was radical surgery and chemoradiotherapy demonstrates limited efficacy for extending survival.

[Calnexin (CNX) enhances the killing effect of CD8+ T cells on colorectal cancer cells by promoting MHC I expression].

Objective To investigate the killing effect and molecular mechanism of aberrant expression of calnexin (CNX) in the colorectal cancer (CRC) on the CD8+ T immune cells. Methods Immunohistochemistry was used to detect CNX protein level in 102 pairs of CRC cancer and adjacent non-cancerous tissues. Western blotting was employed to examine the protein expression of MHC I in the HCT-15 cells overexpressed with CNX or in the SW480 cells whose CNX expressions were knockdown by siRNA. Murine CD8+ T cells isolated from the spleen were cocultured with CT-26 murine CRC cells infected with lentivirus-mediated CNX overexpression. The killing effect of CD8+ T cells on CT-26 cells was determined by cytotoxicity kit. The secretion of interferon γ (IFN-γ) and tumor necrosis factor α (TNF-α) in the culture medium were examined by ELISA. Results The protein level of CNX in colorectal cancer tissues were significantly lower than that in non-cancerous tissues. CNX overexpressed in HCT-15 cells was upregulated and CNX knockdown in SW480 cells downregulated the MHC I expression in these cells. Furthermore, the overexpression of CNX could not only enhance the killing effect of CD8+ T cells on CT-26 cells, but also promote the secretion of IFN-γ and TNF-α from these cells. Conclusion CNX can enhance the killing potential of CD8+ T cells on tumor cells through upregulating the MHC I expression in colorectal cancer cells.

Distribution patterns of macroinvertebrate communities in a Chinese floodgate-regulated river and their relationships with river longitudinal connectivity.

In this study, the Li River and the middle-lower reaches of the Shaying River in the Shaying River basin were selected for an investigation on the effects of floodgates on macroinvertebrate communities; additionally, the relationships among floodgates, macroinvertebrate communities and river longitudinal connectivity were explored. The Li and Shaying rivers had similar ratios of molluscs and scrapers, but their species compositions were significantly different. The water level fluctuations in the Li River were based on natural hydrological characteristics, and these were very different from the fluctuations in the reaches of the Shaying River that were divided by a serious of floodgates. The effects of floodgates resulted in a reduction in the number of taxa, Shannon-Wiener index, Margalef index, and Fisher index and an increase in the Harrison index. The upper reaches of the Li and Saying rivers had similar macroinvertebrate communities, but these were very different from the lower reaches of the Saying River. The total number of species and the number of aquatic insect species increased with the river connectivity gradient and the variations in the α-diversity and ß-diversity indices along reaches confirmed the hypothesis that the longitudinal connectivity of the Shaying River was significantly affected by floodgates. The results of Pearson and PLS tests showed that some plankton variables and physical water parameters could possibly describe how the gradient of river longitudinal connectivity was related to the floodgates in the Shaying River basin. The results of partial correlations showed, even when excluding the effects of water pollution, the protozoa richness and electrical conductivity still had significant influences on the distribution patterns of macroinvertebrate communities. When considering the results of correlation analyses and regression together, these same variables could be used to describe how the gradient of river longitudinal hydrological connectivity is related to floodgates in future studies.

Serological and molecular study of hepatitis E virus among illegal blood donors.

AIM: To investigate the seroprevalence and molecular characteristics of hepatitis E virus (HEV) in the illegal blood donors (IBDs) of central China in the early 1990s. METHODS: A total of 546 blood samples were collected from the IBDs in Maanshan city, a questionnaire was completed by each subject, detailing the age, sex, and periods of blood or plasma donation. Anhui Province and tested for the anti-HEV antibodies. The seropositive samples were subjected to nested reverse transcription-polymerase chain reaction and sequencing to analyze HEV partial genome. RESULTS: The prevalence of IgG and IgM HEV antibody in IBDs was 22.7% and 1.8%, and genotype 4 was the dominant circulating HEV type in IBDs. The prevalence of anti-HEV IgG was significantly related to sex (OR = 4.905, P = 0.004) and increased with age (OR = 2.78, P = 0.022), which ranged from 13.0% in those < 40 years old to 30.6% among older persons aged > 60 years. Moreover, frequency of blood donation was significantly associated with HEV seropositivity (OR = 2.06, P = 0.006). HEV partial sequences of ORF2 and obtained 3 sequences in serum samples of 10 IBDs which developed HEV specific IgM. CONCLUSION: This study helps define one of the possible routes of transmission of sporadic HEV infection and provides guidance to screen HEV in the blood donors so as to guarantee safe blood banks in China.

[Isolation and characterization of Shewanella spp. from patients of food poisoning].

OBJECTIVE: To identify the isolates of Shewanella spp. from specimens of food poisoning based on biological and biochemical analysis. METHODS: Strains were obtained from the investigation on two food poisoning episodes in September and October, 2007 in Ma'anshan city, Anhui province. In accordance with the national standard protocol (GB/T 4789), all specimens were enriched and isolated on selective medium, and the suspected strains were identified by the VITEK-32 and API20E systems. For Shewanella spp. identified by the biochemical system, more characteristics were analyzed using auxiliary biochemical, growth, hemolytic and drug-resistance tests. DNAs of Shewanella spp. were extracted, 16S rDNA was PCR amplified and sequenced with universal 16S rDNA primers. Phylogenetic tree was constructed with MEGA 4.0. RESULTS: After enrichment, all specimens were inoculated to selective medium and Shewanella spp. strains were isolated from 8 samples with single colony on both TCBS and BP media. The characteristics of growth in the Triple Sugar Iron (TSI) agar appeared to have had hydrogen sulfide production but no gas production or positive oxidase. No Shewanella spp. strain was detected in WS, SS and EMB media. The 8 strains were identified as Shewanella algae (S. algae) or Shewanella putrefaciens (S. putrefaciens) by VITEK-32, as S. putrefaciens by API20E system. No other enteropathogenic bacteria, including Vibrio cholerae, Salmonella, Vibrio parahaemolyticus, Proteus vulgaris or Staphylococcus aureus, were detected from those 8 samples. From 16S rDNA phylogenetic trees, 7 out of 8 Shewanella spp. were identified as S. algae, 1 as S. putrefaciens. CONCLUSION: Strains of Shewanella spp. were isolated from samples of the food poisoning episodes, providing a possible clue to investigate the role of Shewanella spp. on food poisoning.

[Cell-surface hydrophobicity and degradation characteristics of hydrophobic hydrocarbon degrading bacteria].

Three high efficient hydrocarbon degrading bacteria named HDB-1, HDB-2, HDB-3 were separated from the oil contaminant soil. This paper studied on the cell-surface hydrophobicity of these three bacteria and environment influence factor by MATH,and the results show that the xylene-water two-phase system is suitable for studying the cell-surface hydrophobicity of three bacteria; the cell-surface hydrophobicities of HDB-1, HDB-2 and HDB-3 are respectively 68.8%, 57.4% and 64.1%; the hydrophobicity changed with the difference of cultivation and time,carbon source, temperature and pH value; the removal ratio of 1 000 mg/L oil content for 6 day can reach 91.6%, 64.5% and 79.8%. The hydrophobicity is related definitely with the degradation of the organic pollutant, and the degradation rate of hydrophobic organic by the bacteria of high hydrophobicity is quicker than that by the bacteria of low hydrophobicity.