Tumor-dilated polymersome nanofactories for enhanced enzyme prodrug chemo-immunotherapy.

Combination chemo-immunotherapy of cancers has attracted great attention due to its significant synergistic antitumor effect. The response rates and therapeutic efficacy of immunotherapy can be enhanced significantly after proper combination with chemotherapy. However, chemo-immunotherapy is frequently limited by severe immune-related adverse events and systemic side toxicity. In this report, efficient nanofactory-directed enzyme prodrug chemo-immunotherapy is demonstrated based on enzyme-loaded tumor-dilatable polymersomes with optimized membrane cross-linking density. Upon intravenous injection of the nanofactories, they can passively accumulate at the tumor site. The tumor pH-responsive nanofactories can swell from ~100 nm to ~200 nm under the trigger of tumor acidity, leading to prolonged retention of up to one week inside tumor tissues. Simultaneously, the membrane permeability of the nanofactories has improved significantly, which allows hydrophilic small molecules to pass across the membranes while keeping the enzymes in the inner cavities. Subsequently, the non-toxic prodrug mixtures of chemo-immunotherapy are administrated three times within 6 days, which are in situ activated by the nanofactories selectively at tumor sites. Activated chemotherapeutic drugs kill cancer cells and generate tumor-associated antigens to promote the maturation of dendritic cells. Activated indoleamine 2, 3-dioxygenase 1 inhibitors reverse the immunosuppressive tumor microenvironment. Finally, primary tumors can be effectively suppressed while causing minimal systemic toxicity. The distant tumors that are established after treatment can also be inhibited completely via activation of antitumor immunity in mice. Thus, the tumor-dilatable polymersome nanofactories with long-term intratumoral retention offer a promising paradigm for enhanced enzyme prodrug chemo-immunotherapy.

Cisplatin resistance reversal in lung cancer by tumor acidity-activable vesicular nanoreactors via tumor oxidative stress amplification.

Drug resistance of cisplatin significantly limits its therapeutic efficacy in clinical applications against different cancers. Herein, we develop a novel strategy to overcome cisplatin drug resistance through sensitizing cisplatin-resistant human lung cancer cells (A549R) under amplified oxidative stress using a vesicular nanoreactor for simultaneous cisplatin delivery and H2O2 generation. We engineer the nanoreactor by the self-assembly of the amphiphilic diblock copolymers to co-deliver glucose oxidase (GOD) and cisplatin (Cis) (Cis/GOD@Bz-V). Cis/GOD@Bz-V was rationally designed to stay impermeable during blood circulation while mild acidity (pH 6.5-6.8) can activate its molecular-weight selective membrane permeability and release cisplatin locally. Diffusion of small molecules such as oxygen and glucose across the membranes can induce the in situ generation of superfluous H2O2 to promote cellular oxidative stress and sensitize A549R cells via activation of pro-apoptotic pathways. Cis/GOD@Bz-V nanoreactors could effectively kill A549R at pH 6.8 in the presence of glucose by the combination of H2O2 generation and cisplatin release. Growth of A549R xenograft tumors can be inhibited efficiently without the obvious toxic side effects via the systemic administration of Cis/GOD@Bz-V. Accordingly, the tumor acidity-activable cisplatin-loaded nanoreactors show great potential to enhance the therapeutic efficacy against cisplatin-resistant cancers.

Accuracy of brush cytology in biliopancreatic strictures: a single-center cohort study.

OBJECTIVE: False positive and negative results are associated with biliary tract cell brushing cytology during endoscopic retrograde cholangiopancreatography (ERCP). The causes are uncertain. The purpose of this study was to evaluate the accuracy of diagnoses made via cell brushing in our center, and to explore the factors influencing diagnosis. METHODS: The clinical data of patients who underwent cell brushing at our center from January 2016 to August 2019 were retrospectively analyzed. These included age, gender, stricture location, thickness of the bile duct wall in the narrow segment, maximum diameter of the biliary duct above the stricture, number of cell brush smears, carbohydrate antigen 19-9, and carcinoembryonic antigen. Positive brush cytology results were compared with results of surgical histology or tumor biopsy as well as with the patient's clinical course. RESULTS: Of the 48 patients who underwent cell brushing cytology, 27 (56.3%) had positive results. The sensitivity and specificity of biliary duct cell brushing was 79.4%, and 85.7%, respectively. None of the above-mentioned factors were associated with positive cytology brushing results. CONCLUSIONS: Cell brushing cytology remains a reliable method for diagnosis of pancreaticobiliary malignancies.

Diagnostic accuracy of endoscopic ultrasound-guided fine-needle aspiration: A single-center analysis.

Background: Endoscopic ultrasound-guided fine-needle aspiration biopsy (EUS-FNAB) has become an important modality for identification of intra-abdominal masses. This study analyzed the accuracy of EUS-FNAB in a single medical center and explored factors related to positive diagnosis. Materials and methods: In total, 77 patients with EUS-FNAB were retrospectively reviewed from July 2016 to February 2020. "Atypical (tends to be neoplasm/malignancy)," "suspicious (first consider neoplasm/malignancy)," and "malignant" were defined as positive cytology. The final diagnoses were based on histopathologic examination. The positive rate of EUS-FNAB for the diagnosis of neoplasm and its associations with age, sex, target puncture mass size, liver function, tumor markers, albumin, hypertension, and diabetes were examined. Results: Accuracy, sensitivity, specificity, positive predictive value, and negative predictive value of EUS-FNAB cytologic diagnoses in all patients were 77.9% (60/77), 76.1% (54/71), 100%, 100%, and 26.1% (6/23), respectively. Accuracy, sensitivity, specificity, positive predictive value, and negative predictive value of EUS-FNAB cytologic diagnoses in the pancreas were 80.0% (48/60), 79.3% (46/58), 100%, 100%, and 14.3% (2/14), respectively. The results of EUS-FNAB in pancreatic masses showed that the level of CA19-9 was higher in the true positive group than in the false-negative group (p<0.05). There were no factors associated with the true positive cytologic diagnoses (p>0.05). Conclusions: Our single-medical center study showed that EUS-FNAB is an accurate diagnostic procedure for the evaluation of intra-abdominal masses. Further follow-up is required to explore factors associated with the true positive cytology.

Macrovascular Endothelial Cells Enhance the Motility of Liver Cancer Cells by Up-regulation of MMP-3, Activation of Integrin/FAK Signaling Pathway and Induction of Non-classical Epithelial-mesenchymal Transition.

Background: Liver cancer with portal vein tumor thrombus (PVTT) indicates a serious prognosis. The molecular mechanism of PVTT formation is not totally clarified, the invasion of blood vessels by liver cancer cells is the key step and portal vein endothelial cells plays critical role. Methods: Conditioned medium (CM) of human umbilical vein endothelial cells (HUVEC) were used to culture liver cancer cells and prostate cancer cells for cell motility and viability analysis for the purpose of simulating the role of macrovascular endothelial cells in the development of liver cancer. Results: HUVEC-CM caused long spindle-shaped changes in liver cancer cells; the invasion and migration ability of Bel-7402 and MHCC-LM3 (cultured in HUVEC-CM) increased significantly. Integrins/FAK (focal adhesion kinase) signaling pathway was activated and MMP-3 was up-regulated. However, classical epithelial-mesenchymal transition (EMT) did not involve. HUVEC-CM caused a decrease of cell population in G1- and S-phase of Bel-7402, it also caused an accumulation of cell population in G1 phase and a decrease of cell population in S-phase of MHCC-LM3, MHCC-97L and DU-145. HUVEC-CM promotes apoptosis of Bel-7402 and MHCC-97L and the nude mouse tumorigenic experiment did not find that the HUVEC-CM increase the tumorigenic ability of liver cancer cells. Conclusion: HUVEC may provide an easy-to-adhere roadbed for liver cancer cells invasion of blood vessels by altering extracellular matrix (ECM), activating integrins/FAK pathway and inducing non-classical EMT. The effect of HUVEC-CM on cell viability was cancer cell type dependent. It is a meaningful glance at the mechsanism of PVTT.

MRC-5 Cancer-associated Fibroblasts Influence Production of Cancer Stem Cell Markers and Inflammation-associated Cell Surface Molecules, in Liver Cancer Cell Lines.

Background: Current opinion suggests that expansion of cancer stem cells (CSCs) and activation of pro-tumoral inflammation cascade correlate with cancer progression. Materials and methods: We explored the possible contributions of MRC-5 cancer-associated fibroblasts to the expression profiles of CSC markers and inflammation-associated cell surface molecules. The liver cancer cell lines Bel-7402, SMMC-7721, MHCC-LM3, and HepG2 cultured in conditioned medium (CM) from MRC-5 served as test groups, whereas the liver cancer cell lines cultured in normal medium served as control groups. Results: Flow cytometry revealed that the proportions of CD90+ cells were significantly higher in MHCC-LM3-(MRC-5)-CM and HepG2-(MRC-5)-CM cells, and moderately higher in Bel-7402-(MRC-5)-CM and SMMC-7721-(MRC-5)-CM cells, than in controls. The CD90+/CD45- proportions were elevated in Bel-7402-(MRC-5)-CM and MHCC-LM3-(MRC-5)-CM cells, but reduced in HepG2-(MRC-5)-CM and SMMC-7721-(MRC-5)-CM cells, as compared to controls. Western blotting indicated that Nanog was downregulated in MHCC-LM3-(MRC-5)-CM and HepG2-(MRC-5)-CM cells, compared to controls; that POU5F1 (OCT4/3) was downregulated in MHCC-LM3-(MRC-5)-CM, but upregulated in Bel-7402-(MRC-5)-CM and HepG2-(MRC-5)-CM cells, compared to controls, and that CK19 was upregulated in Bel-7402-(MRC-5)-CM and MHCC-LM3-(MRC-5)-CM cells, compared to controls. Proportions of cells expressing Toll-like receptor-1+ (TLR1) and TLR4 were significantly higher in MHCC-LM3-(MRC-5)-CM cells, and moderately higher in HepG2-(MRC-5)-CM cells, than controls. However, the TLR1+ and TLR4+ proportions were lower in Bel-7402-(MRC-5)-CM and SMMC-7721-(MRC-5)-CM cells than controls. Proportions of CD25+ cells were reduced in HepG2-(MRC-5)-CM and SMMC-7721-(MRC-5)-CM cells, but elevated in MHCC-LM3-(MRC-5)-CM and Bel-7402-(MRC-5)-CM cells, compared to controls. Proportion of CD61+ cells was higher in liver cancer cells cultured in MRC-5-CM than in controls. Proportion of CD14+ cells was lower in HCC cells cultured in MRC-5-CM than in controls. Conclusion: MRC-5 extensively affected the production of CSC markers and inflammation-associated cell surface molecules. Tumor-targeting molecular therapies should consider these findings.

ROS-Responsive Polymeric Nanocarriers with Photoinduced Exposure of Cell-Penetrating Moieties for Specific Intracellular Drug Delivery.

In situ modulation of the surface properties on the micellar drug delivery nanocarriers offers an efficient method to improve the drug delivery efficiency into cells while maintaining stealth and stability during blood circulation. Light has been demonstrated to be a temporally and spatially controllable tool to improve cellular internalization of nanoparticles. Herein, we develop reactive oxygen species (ROS)-responsive mixed polymeric micelles with photoinduced exposure of cell-penetrating moieties via photodynamic ROS production, which can facilitate cellular internalization of paclitaxel (PTX) and chlorin e6 (Ce6)-coloaded micelles for the synergistic effect of photodynamic and chemotherapy. The thioketal-bond-linked block polymers poly(ε-caprolactone)-TL-poly(N,N-dimethylacrylamide) (PCL-TL-PDMA) with a long PDMA block are used to self-assemble into mixed micelles with PCL-b-poly(2-guanidinoethyl methacrylate) (PCL-PGEMA) consisting of a short PGEMA block, which are further used to coencapsulate PTX and Ce6. After intravenous injection, prolonged blood circulation of the micelles guarantees high tumor accumulation. Upon irradiation by 660 nm light, ROS production of the micelles by Ce6 induces cleavage of PDMA to expose PGEMA shells for significantly improved cellular internalization. The combination of photodynamic therapy and chemotherapy inside the tumor cells achieves improved antitumor efficacy. The design of ROS-responsive mixed polymeric nanocarriers represents a novel and efficient approach to realize both long blood circulation and high-efficiency cellular internalization for combined photodynamic and chemotherapy under light irradiation.

COL6A1 promotes metastasis and predicts poor prognosis in patients with pancreatic cancer.

Pancreatic cancer is one of the most aggressive cancers worldwide with a high mortality rate. Prognosis remains poor even in this era of advanced medicine mainly due to early metastasis and invasion. The present study aimed to explore and validate predictors of distant metastasis and prognosis in pancreatic cancer. In our preliminary experiment, we established a novel metastatic pancreatic cancer cell line BxPC­M8 from parent BxPC­3 cells. Via whole genome sequencing, RT­qPCR, western blotting, migration and invasion assays, we initially found that BxPC­M8 shared similar biological characteristics to BxPC­3, but only differed in enhanced metastatic and invasive capabilities with a significant increase in collagen type VI α1 chain (COL6A1) expression. Knockdown of COL6A1 via small interfering RNA led to a significant decrease in migration and invasion of BxPC­M8 cells, suggesting suppressed epithelial­mesenchymal transition. Furthermore, a significant increase in COL6A1 expression was observed in cancerous tissue compared with paracancerous tissue (40.7 vs 3.7, P=0.001). Additionally, its expression was observed to be significantly associated with distant metastasis and vascular invasion at the time of surgery. Multivariate analysis revealed that COL6A1 expression (hazard ratio 1.90, 95% confidence interval 1.04­3.47, P=0.037) is an independent predictor of overall survival (OS). The median OS observed for COL6A1+ and COL6A1­ patients was found to be 8±4 and 14±7 months (P=0.021), respectively. Of note, we identified that COL6A1 expression in tissue samples was associated with significantly reduced OS (P=0.001), demonstrating that COL6A1 may serve an important role in the metastatic process and could be considered as a predictor of poor outcomes in patients with pancreatic cancer. In addition, our findings suggest that COL6A1 could be an indicator of distant metastasis and a valid prognostic predictor in such patients; however, further investigation is required.

Serum Biomarkers AFP, CEA and CA19-9 Combined Detection for Early Diagnosis of Hepatocellular Carcinoma.

BACKGROUND: We aimed to evaluate the whether AFP levels alone is an adequate screening indicator, or a combination of Generally, alpha-fetoprotein (AFP), CA19-9 and CEA could provide a better diagnostic tool in detecting and screening asymptomatic patients with primary hepatic cancer (PHC), and also evaluate the correlation of degree of differentiation with serum biomarker levels. METHODS: We retrospectively reviewed the medical records of 1362 patients form 2014-2018 who visited the first Affiliated Hospital of Zhejiang University, Hangzhou, China for health check-ups or were diagnosed with cancer or cirrhosis. We then analyzed preoperative tumor markers level of AFP, CA19-9, and CEA. The standard reference values (AFP ≤20 ng/L CEA ≤ 5 ng/L, and CA19-9 ≤ 37 U/mL) were as positive or negative cut off values. Further, the histological sections of patients were categorized and correlated them with the three serum biomarkers. RESULTS: Serum AFP, CEA, and CA19-9 levels in the PHC group were significantly higher compared to those with liver cirrhosis and healthy control groups (P < 0.03). With AFP as a single tumor marker for PHC diagnosis, it had a sensitivity of 63.3% with a specificity of 80.8%. AFP combined with CA19-9 and CEA showed specificity of 100%, a sensitivity 2.5% with the positive and negative predictive values of 100% and 22% respectively. Furthermore, histological evaluation revealed the highest AFP level of 9366.14±23902.61 ng/L associated with poorly differentiated HCC, while well-differentiated HCC, had the lowest mean AFP level of 45.19±181.27 ng/L. CONCLUSION: Combined serum levels of AFP, CA19-9 and CEA does not provide a superior advantage over AFP alone as a screening and diagnostic tool for HCC detection.

Reduction-Responsive Polymer Prodrug Micelles with Enhanced Endosomal Escape Capability for Efficient Intracellular Translocation and Drug Release.

High-efficiency endosomal escape of drug delivery nanocarriers for glutathione-based reduction-responsive drug release in cytoplasm can significantly enhance the therapeutic efficacy of the loaded therapeutic drugs. In this report, we develop the polymer prodrug micelles self-assembled from the amphiphilic block copolymer prodrug, PEG-b-P(CPTM-co-ImOAMA), consisting of poly(ethylene glycol) (PEG) and copolymerized segments of disulfide bond-linked camptothecin methacrylate monomer (CPTM) and 1-(1H-imidazole-4-yl)-2-(octylamino)-2-oxoethyl methacrylate (ImOAMA). After cellular internalization through endocytosis, PEG-b-P(CPTM-co-ImOAMA) micelles are trapped in endosomes inside the tumor cells. The endosomal pH can trigger the protonation of the imidazole moieties of PImOAMA segments, which may facilitate endosome escape through the proton sponge effect and the improved interactions between protonated imidazole groups, hydrophobic octyl moieties, and endosomal membranes. Moreover, the high concentration of glutathione in the cytoplasm of cancer cells can trigger the release of active camptothecin (CPT) through cleavage of the disulfide linkers from PCPTM. The in vitro results showed that PEG-b-P(CPTM-co-ImOAMA) micelles could be effectively internalized into cells followed by endosomal escape, which contributed to the significantly improved cancer cell-killing efficacy. Moreover, in vivo studies confirmed that the PEG-b-P(CPTM-co-ImOAMA) micelles realized efficient tumor growth inhibition without obvious side toxicity. Therefore, the proposed reduction-responsive polymeric prodrug micelles with high endosomal escape capability could provide a brilliant potential in a drug delivery platform to achieve enhanced antitumor efficacy.