CCR7 high expression leads to cetuximab resistance by cross-talking with EGFR pathway in PI3K/AKT signals in colorectal cancer

Cetuximab (C225), an anti-Epidermal Growth Factor receptor (EGFR) monoclonal antibody, has been widely used as a routine treatment for patients with metastatic colorectal cancer (mCRC); However, many patients who initially respond to cetuximab acquire resistance. The purpose of this study was to characterize new mechanism of acquired Cetuximab resistance. Firstly, tissue microarrays (TMA) comprising 191 CRC patients was constructed to evaluate the expression of chemokine receptor 7 (CCR7) by using immunohistochemistry (IHC). In CRC tumor tissues, CCR7 was significantly over-expressed compared with paired normal tissues (P < 0.001), and correlated with the infiltration depth (P = 0.03) and the regional lymph node metastasis (P = 0.006). Significant differences were also found in forms of overall survival (OS) and disease-free survival (DFS) between normal and tumor tissues (P < 0.001). More interestingly, EGFR was also highly expressed and co-localized with CCR7 in the tumor tissues from the patients who were insensitive to Cetuximab treatment. Secondly, we further explored the relationship between CCR7 expression and Cetuximab resistance by two CCR7 positive CRC cell lines, Caco-2 with wild-type KRAS (KRAS^wt ) and HCT116 with mutated KRAS (KRAS^G13D ). By the treatment of secondary lymphoid tissue chemokine (SLC, an exogenous high-affinity legend of CCR7), the inhibition rate of Cetuximab significantly decreased in both cells. Furthermore, the activation of SLC/CCR7 axis promoted epithelial mesenchymal transformation (EMT) in CRC tumor cells by increasing the expression of Twist and β-catenin. By using of CCR7 neutralizing antibody and p-AKT inhibitor rescued the above effects. These findings suggested that CCR7 was a key factor in those CRC patients, who have poorer reaction to Cetuximab. So combined inhibition of CCR7 and p-AKT will represent a rational therapeutic strategy for Cetuximab resistance patients.

Zinc-α2-glycoprotein 1 promotes EMT in colorectal cancer by filamin A mediated focal adhesion pathway

Liver metastasis is the main reason for the poor prognosis of colorectal cancer, and identifying molecules involved in liver metastases of colorectal cancer may provide effective therapeutic targets. Zinc-α2-glycoprotein 1(AZGP1) is a candidate biomarker for diagnosis and prognosis in cancer. However, its function and molecular mechanism in metastatic colorectal cancer remains largely unknown. We previously found that up-regulated AZGP1 promotes proliferation, migration and invasion in colorectal cancer cell line, here we elucidated the mechanism of AZGP1 in regulating metastasis. In this article, we found that AZGP1 was also highly expressed in colorectal cancer tissues with liver metastasis relative to those without metastasis, and abundant expression of AZGP1 was associated with poor prognosis, also, AZGP1 down regulation prevented cell metastasis in vivo and in vitro. We further demonstrated that AZGP1 promotes metastasis by regulating the epithelial-mesenchymal transition (EMT) and associating with molecules involved in the focal adhesion pathway, including the adhesion molecule FLNA, which acts as an important protein interactor. More importantly, AZGP1 down regulation inhibited the phosphorylation of FLNA mediated by the restrain of PAK2 kinase, thereby inducing its proteolysis and subsequently affecting its subcellular localization, where it regulates the EMT and promotes metastasis. Collectively, these results highlight AZGP1 as a new and promising therapeutic molecule for liver metastatic colorectal cancer.

Isolation of H8N4 avian influenza virus from wild birds in Shanghai, China

The H8 subtype viruses are rarely isolated from wild ducks. Shanghai is one of the important wintering or stopover sites on the East Asia-Australia Migration Flyway. An influenza virus, subtype H8N4, was firstly isolated from a common teal (Anas crecca) in Shanghai during 2017-2018 in this study. To clarify the genetic characteristics of the H8N4 virus, the whole genome sequences were analyzed. Phylogenetic analysis of the hemagglutinin and neuraminidase genes showed that they shared highest nucleotide identity (99.19%-99.64%) with the Japan duck-origin H8N4 virus collected in 2016 (A/duck/Aichi/231003/2016) and belonged to the Eurasian-like avian lineage. Six other genes of the H8N4 isolated virus were all highly similar to the corresponding genes of a wide range of AIV subtypes including H9N2, H5N7, H3N8, H1N2, H4N6 and H1N1. The results indicated that the H8N4 virus was a multiple reassortant virus. The study emphasized that the continuous surveillance of influenza virus in wild birds should be strengthened. Keywords: avian influenza virus; H8N4; phylogenetic analysis; Shanghai.

Tumor-associated Macrophages as Prognostic and Predictive Biomarkers for Postoperative Adjuvant Chemotherapy in Patients with Stage II Colon Cancer

PURPOSE

For stage II colon cancer, the efficacy of postoperative adjuvant chemotherapy remains controversial. It is well known that tumor-associated macrophages (TAMs) are important in tumor progression. In this study, TAMs were investigated as prognostic and predictive biomarkers for the efficacy of adjuvant chemotherapy for stage II colon cancer after radical resection.

EXPERIMENTAL DESIGN

This study enrolled two independent cohorts of consecutive patients from one medical center with pathologic stage II colon cancer after radical resections. Macrophages were detected using IHC staining of CD68 and CD206. Infiltration densities of CD68⁺ TAMs, CD206⁺ TAMs, and ratio of CD206⁺ TAMs/CD68⁺ TAMs (CD206/CD68 ratio) were calculated as prognostic and predictive biomarkers.

RESULTS

The primary and validation cohorts consisted of 521 and 314 patients, respectively. In both cohorts, high CD206/CD68 ratio was significantly associated with poor disease-free survival (DFS) and overall survival (OS). As an independent risk factor, CD206/CD68 ratio also had significantly better prognostic efficacy than CD68⁺ TAM density, CD206⁺ TAM density, and traditional clinicopathologic high-risk factors. Moreover, adjuvant chemotherapy significantly improved DFS and OS for patients with high CD206/CD68 ratio but not for those with low CD206/CD68 ratio. The interaction analyses were also significant for DFS. In subgroup analysis, CD206/CD68 ratio was still a significant predictor for adjuvant chemotherapy for patients in traditional high-risk group of recurrence (significant interaction for DFS).

CONCLUSIONS

For stage II colon cancer, CD206/CD68 ratio is a better prognostic and predictive biomarker for postoperative adjuvant chemotherapy. Together with clinicopathologic high-risk factors, it will aid in precision treatment.

Pharmacokinetic and Pharmacogenetic Factors Contributing to Platelet Function Recovery After Single Dose of Ticagrelor in Healthy Subjects

Objectives: This study aimed to elucidate the contribution of candidate single nucleotide polymorphisms (SNPs) related to pharmacokinetics on the recovery of platelet function after single dose of ticagrelor was orally administered to healthy Chinese subjects.

Methods: The pharmacokinetic profiles of ticagrelor and its metabolite AR-C124910XX (M8), and the platelet aggregation (PA), were assessed after 180 mg of single-dose ticagrelor was orally administered to 51 healthy Chinese subjects. Effects of CYP2C19^*2, CYP2C19^*3, CYP3A5^*3, UGT1A1^*6, UGT1A1^*28, UGT2B7^*2, UGT2B7^*3, SLCO1B1 388A>G, and SLCO1B1 521T>C, on the pharmacokinetics of ticagrelor and M8, and platelet function recovery were investigated.

Results: The time to recover 50% of the maximum drug effect (RT₅₀) ranging from 36 to 126 h with 46.9% CV had a remarkable individual difference and was positively associated with the half-life (t_1/2) of M8 (r = 0.3901, P = 0.0067). The time of peak concentration (T_max) of ticagrelor for CYP2C19^*3 GG homozygotes was significantly higher than that of GA heterozygotes (P = 0.0027, FDR = 0.0243). Decreased peak concentration (C_max) of M8 was significantly associated with SLCO1B1 388A>G A allele (P = 0.0152, FDR = 0.1368). CYP2C19^*2 A was significantly related to decreased C_max of M8 (P = 0.0455, FDR = 0.2048). While, the influence of these nine SNPs on the recovery of platelet function was not significant.

Conclusion: Our study suggests that the elimination of M8 is an important factor in determining the recovery of platelet function. Although CYP2C19 and SLCO1B1 genetic variants were related to the pharmacokinetics of ticagrelor or M8, they did not show a significant effect on the platelet function recovery in this study.

Clinical Trial Registration:https://clinicaltrials.gov/ct2/show/NCT03092076, identifier: NCT03092076

Semi-dominant mutation in the cysteine-rich receptor-like kinase gene, ALS1, conducts constitutive defence response in rice

Plants have evolved a sophisticated two-branch defence system to prevent the growth and spread of pathogen infection. The novel Cys-rich repeat (CRR) containing receptor-like kinases, known as CRKs, were reported to mediate defence resistance in plants. For rice, there are only two reports of CRKs. A semi-dominant lesion mimic mutant als1 (apoptosis leaf and sheath 1) in rice was identified to demonstrate spontaneous lesions on the leaf blade and sheath. A map-based cloning strategy was used for fine mapping and cloning of ALS1, which was confirmed to be a typical CRK in rice. Functional studies of ALS1 were conducted, including phylogenetic analysis, expression analysis, subcellular location and blast resistance identification. Most pathogenesis-related (PR) genes and other defence-related genes were activated and up-regulated to a high degree. ALS1 was expressed mainly in the leaf blade and sheath, in which further study revealed that ALS1 was present in the vascular bundles. ALS1 was located in the cell membrane of rice protoplasts, and its mutation did not change its subcellular location. Jasmonic acid (JA) and salicylic acid (SA) accumulation were observed in als1, and enhanced blast resistance was also observed. The mutation of ALS1 caused a constitutively activated defence response in als1. The results of our study imply that ALS1 participates in a defence response resembling the common SA-, JA- and NH1-mediated defence responses in rice.

Etching gas-sieving nanopores in single-layer graphene with an angstrom precision for high-performance gas mixture separation

One of the bottlenecks in realizing the potential of atom-thick graphene membrane for gas sieving is the difficulty in incorporating nanopores in an otherwise impermeable graphene lattice, with an angstrom precision at a high-enough pore density. We realize this design by developing a synergistic, partially decoupled defect nucleation and pore expansion strategy using O₂ plasma and O₃ treatment. A high density (ca. 2.1 × 10¹² cm^-2) of H₂-sieving pores was achieved while limiting the percentage of CH₄-permeating pores to 13 to 22 parts per million. As a result, a record-high gas mixture separation performance was achieved (H₂ permeance, 1340 to 6045 gas permeation units; H₂/CH₄ separation factor, 15.6 to 25.1; H₂/C₃H₈ separation factor, 38.0 to 57.8). This highly scalable pore etching strategy will accelerate the development of single-layer graphene-based energy-efficient membranes.

[The treatment of nose-eye correlated diseases with external nasal incision combined with nasal cavity approach surgery through endoscope]

Objective:To explore the indications and characteristics for the treatment of nose-eye correlated diseases with endoscopic surgery through external nasal incision combined with nasal cavity approach.Method:The clinical data of 13 patients whom hospitalized in our department and treated by endoscopic surgery through external nasal incision combined with nasal cavity approach since October 2011, were retrospectively analyzed and the characteristics of different pathological changes, clinical manifestations, surgical approach and follow-up results were summarized.Four cases of patients underwent endoscopic surgery through nasal cavity and lacrimal caruncle conjunctival incision, 4 cases received bone fracture reduction and DCR with endoscope through double path of nasal cavity and the original trauma wound, 2 cases with endoscopic bone tumor resection through nasal cavity and external nasal incision, the rest of the 3 cases with endonasal endoscopic and peri-orbit incision surgery.Result:Two cases of tumor patients showed no recurrence followed up for 1.5 to 2 years; the diplopia disappeared in 2 cases of orbital medial wall fracture; surgeries of 4 cases of orbital wall fracture with lacrimal duct obstruction patients, 3 cases succeeded, 1 case failed and change into dacryocystorhinotomy with external nasal incision, and epiphora of all patients vanished; all of the patients of sinus osteoma, foreign bodies and abscess were cured and symptoms disappeared; the symptoms of ectopic meningioma patient gradually died down with eyebrow scars left.Conclusion:The surgery with external nasal incision combined with nasal cavity approach through endoscope to treat noseeye correlated diseases can effectively deal with relevant pathological changes, with the advantages of clear operation field and less damage, but its exact indications and surgical methods still need to be further explored.

Patients with RAS wild-type right-sided unresectable liver-confined mCRC also benefit from cetuximab plus chemotherapy in first-line treatment

Growing evidence indicates that primary tumor location of metastatic colorectal cancer (mCRC) can affect response to specific therapy. This study aimed to assess the impact of primary tumor location on efficacy of cetuximab in Chinese patients with mCRC. We included patients with RAS wild-type liver-limited mCRC treated with first-line cetuximab plus chemotherapy or chemotherapy alone between June 2008 and December 2016. All patients were categorized as having left-sided tumors or right-sided tumors. Progression free survival (PFS), overall survival (OS), objective response rate (ORR) and conversion rate of surgery for liver metastases was analyzed according to tumor location and treatment. Right-sided tumors were characterized with larger primary tumor, poorer differentiation, more lymph node metastases and larger and more liver metastases. For patients with left-sided tumors (N=233), addition of cetuximab to chemotherapy significantly improved ORR (68.9% vs. 30.6%, OR=5.01, P < 0.001), conversion rate of liver surgery (33.5% vs. 10.8%, OR=4.18, P < 0.001), PFS (12.1 months vs. 6.1 months, HR=0.42, P < 0.001), and OS (not evaluable vs. 23.1 months, HR=0.31, P < 0.001). Among patients with right-sided tumors (N=85), cetuximab plus chemotherapy, compared with chemotherapy alone, also significantly improved ORR (56.8% vs. 29.3%, OR=3.18, P=0.010), PFS (9.3 months vs. 5.1 months, OR=0.57, P=0.012) and OS (25.3 months vs. 16.8 months, HR=0.56, P=0.032) but conversion rate of liver surgery (20.5% vs. 9.8%, HR=2.38, P=0.171). Our results demonstrated differential effect of cetuximab on efficacy outcomes based on tumor sidedness. Also, we found that patients with right-sided tumors also benefit from cetuximab plus chemotherapy but not as great as left-sided tumors and in general, did worse. In conclusion, findings of previous studies about differential effect of anti-EGFR therapy based on tumor sidedness are applicable to an Asian population.

Low tumor purity is associated with poor prognosis, heavy mutation burden, and intense immune phenotype in colon cancer

Purpose

Tumor purity is defined as the proportion of cancer cells in the tumor tissue. The impact of tumor purity on colon cancer (CC) prognosis, genetic profile, and microenvironment has not been thoroughly accessed.

Materials and methods

Clinical and transcriptomic data from three public datasets, GSE17536/17537, GSE39582, and TCGA, were retrospectively collected (n=1,248). Tumor purity of each sample was inferred by a computational method based on transcriptomic data. Survival-related analyses were performed on microarray dataset containing GSE17536/17537 and GSE39582 (n=794), whereas TCGA dataset was utilized for subsequent genomic analysis (n=454).

Results

Right-sided CC patients showed a significantly lower tumor purity. Low purity CC conferred worse survival, and tumor purity was identified as an independent prognostic factor. Moreover, high tumor purity CC patients benefited more from adjuvant chemotherapy. Subsequent genomic analysis found that the mutation burden was negatively associated with tumor purity, with only APC and KRAS significantly more mutated in high purity CC. However, no somatic copy number alteration event was correlated with tumor purity. Furthermore, immune-related pathways and immunotherapy-associated markers (programmed cell death protein 1 [PD-1], programmed death-ligand 1 [PD-L1], cytotoxic T-lymphocyte-associated protein 4 [CTLA-4], Lymphocyte-activation gene 3 [LAG-3] and T-cell immunoglobulin and mucin-domain containing-3 [TIM-3]) were highly enriched in low purity samples. Notably, the relative proportion of M2 macrophages and neutrophils, which indicated worse survival in CC, was negatively associated with tumor purity.

Conclusion

Tumor purity exhibited potential value for CC prognostic stratification as well as adjuvant chemotherapy benefit prediction. The relative worse survival in low purity CC may attribute to higher mutation frequency in key pathways and purity-related microenvironmental changing.

Differences in clinical characteristics and mutational pattern between synchronous and metachronous colorectal liver metastases

Purpose

To investigate differences in clinical characteristics and mutational patterns between synchronous and metachronous colorectal liver metastases (CLMs).

Patients and methods

From June 2008 to December 2014, patients with RAS wild-type CLMs treated at Zhongshan Hospital, Fudan University were included. DNA extracted from formalin-fixed paraffin-embedded tissue of primary tumors was sequenced with next-generation sequencing for single-nucleotide polymorphism of 96 genes according to custom panel. Mutations were compared between synchronous and metachronous liver metastases and correlated with clinical characteristics.

Results

A total of 161 patients were included: 93 patients with synchronous CLM and 68 patients with metachronous CLM. Patients with metachronous CLM were obviously elder. For pathology of primary tumors, synchronous CLMs were larger in size, poorly differentiated, and more frequently local advanced and lymph node positive. For evaluation of liver metastases, synchronous CLM had more and larger metastatic lesions. The median number of mutations in synchronous CLMs was significantly higher than in metachronous group (22 vs. 18, p<0.001). EGFR rs2227983 is the most prevalent mutation in both groups and only a part of prevalent mutations is shared in both groups. Prevalent mutations were correlated with many clinical characteristics. EGFR rs2227983, RBMXL3 rs12399211, and PTCH1 rs357564 were prognostic for latency of metachronous CLM.

Conclusion

Clinically, synchronous CLMs, compared with metachronous CLMs, were younger and showed heavier tumor burden for both primaries and liver metastases. Genetically, we identified different mutational patterns between synchronous and metachronous CLMs and several correlations between mutations and clinical characteristics. Further researches were needed to confirm these potential key mutations of CLMs.

Low tumor infiltrating mast cell density confers prognostic benefit and reflects immunoactivation in colorectal cancer

The role of mast cells (MCs) in colorectal cancer (CRC) progression was controversial. Thus, our study was designed to evaluate the prognostic value of MCs as well as their correlation with immune microenvironment. A retrospective cohort of CRC patients of stages I-IV was enrolled in our study. Consecutive patients (854) were divided into training set (427 patients) and validation set (427 patients) randomly. The findings were further validated in a GEO cohort, GSE39582 (556 patients). The mast cell density (MCD) was measured by immunohistochemical staining of tryptase or by CIBERSORT algorithm. Low MCD predicted prolonged overall survival (OS) in training and validation set. Moreover, MCD was identified as an independent prognostic indicator in both sets. Better stratification for CRC prognosis can be achieved by building a MCD based nomogram. The prognostic role of MCD was further validated in GSE39582. In addition, MCD predicted improved survival in stages II and III CRC patients receiving adjuvant chemotherapy (ACT). Multiple immune pathways were enriched in low MCD group while cytokines/chemokines promoting anti-tumor immunity were highly expressed in such group. Furthermore, MCD was negatively correlated with CD8+ T cells infiltration. In conclusion, MCD was identified as an independent prognostic factor, as well as a potential biomarker for ACT benefit in stages II and III CRC. Better stratification of CRC prognosis could be achieved by building a MCD based nomogram. Moreover, immunoactivation in low MCD tumors may contributed to improved prognosis.

High Plasma Exposure of Statins Associated With Increased Risk of Contrast-Induced Acute Kidney Injury in Chinese Patients With Coronary Artery Disease

The role of statins in reducing the incidence of contrast-induced acute kidney injury (CI-AKI) remains controversial. We sought to evaluate the association between CI-AKI and high plasma exposure of statins in coronary artery disease (CAD) patients undergoing coronary angiography (CAG). This association was first evaluated in 1,219 patients with CAD receiving atorvastatin (AT) therapy and validated in 635 patients receiving rosuvastatin (RST) therapy. The plasma concentrations of statins were quantified using validated UPLC-MS/MS methods and CI-AKI incidence was assessed during the first 48 h postoperatively. Among all participants (n = 1,854), AKI occurred in 57 of 1219 (4.7%) in the AT cohort and 30 of 635 (4.7%) in the RST cohort. High plasma AT-all exposure was associated with increased risk of CI-AKI (odds ratio [OR]: 2.265; 95% confidence interval [CI]: 1.609–3.187; p < 0.0001). Plasma AT-all concentration in the CI-AKI group (22.40 ± 24.63 ng/mL) was 2.6-fold higher than that in the control group (8.60 ± 9.65 ng/mL). High plasma RST exposure also significantly increased the risk of CI-AKI (OR: 2.281; 95% CI: 1.441–3.612; p = 0.0004). We further divided patients into two subgroups for each statin according to baseline renal function, and association between high plasma statin exposure and CI-AKI still remained highly significant in both subgroups. This study suggests for the first time that high plasma exposure of statins may significantly increase the risk of CI-AKI. Statins should be used with greater caution in CAD patients undergoing CAG to reduce the occurrence of CI-AKI.

Tumor-associated macrophages as predictive biomarkers for postoperative adjuvant chemotherapy in patients with stage II colon cancer

620

Background: For stage II colon cancer, the effect of postoperative adjuvant chemotherapy is still controversial. It is well known that tumor-associated macrophages (TAMs) play an important role in tumor progression. The aim of this study is to determine the effect of TAMs as predictor for adjuvant chemotherapy for stage II colon cancer. Methods: From July 2009 to June 2012, 521 patients with pathological stage II colon cancer were included. TAMs were detected using tissue microarray and immunohistochemistry (all TAMs detected by CD68; M2 subtype detected by CD206). The density of CD68+ TAMs, CD206+ TAMs and the ratio of CD206+ TAMs / CD68+ TAMs (CD206 / CD68 ratio) were calculated. The cut-off values were defined using X-Tile software. Results: High CD206+ TAMs density and high CD206 / CD68 ratio were significantly associated with reduced disease-free survival (DFS, P < 0.001 and P < 0.001, respectively) and overall survival (OS, P < 0.001 and P < 0.001, respectively). And CD206 / CD68 ratio had a better prognostic power. Furthermore, for patients with low CD206 / CD68 ratio, adjuvant chemotherapy made no benefit. But for high CD206 / CD68 ratio, adjuvant chemotherapy significantly improved DFS and OS (as shown in Table 1). In subgroup analysis, for T3 with high-risk factors or T4 tumors, CD206 / CD68 ratio was also a significant predictor for adjuvant chemotherapy (interaction P = 0.024 in DFS). Conclusions: For stage II colon cancer, CD206 / CD68 ratio was a good prognostic and predictive biomarker for adjuvant chemotherapy. Together with clinicopathological high-risk factors, it might facilitate patient counselling and individualise management. [Table: see text]

Silencing homeobox C6 inhibits colorectal cancer cell proliferation

Homeobox C6 (HOXC6), a member of the homeobox family that encodes highly conserved transcription factors, plays a vital role in various carcinomas. In this study, we used a tissue microarray (TMA) consisting of 462 CRC samples to demonstrate that HOXC6 is more abundantly expressed in colorectal cancer (CRC) tissues than adjacent normal mucosa. Clinicopathological data indicated that higher HOXC6 expression correlated with poor overall survival and was associated with primary tumor location in the right colon, primary tumor (pT) stage 3/4 and primary node (pN) stage 1/2. Multivariate analysis showed that high HOXC6 expression was an independent risk factor for poor CRC patient prognosis. HOXC6 downregulation via lentivirus-mediated expression of HOXC6-targeting shRNA reduced HCT116 cell viability and colony formation in vitro, and reduced growth of subcutaneous xenografts in nude mouse. HOXC6 thus appears to promote CRC cell proliferation and tumorigenesis through autophagy inhibition and mTOR pathway activation.

Total synthesis of teixobactin and its stereoisomers

The total syntheses of teixobactin and a series of its stereoisomers at positions 2, 5, 6, 10 and 11 were achieved via a combined strategy of solution and solid phase peptide synthesis.