Discovery of highly potent and selective 7-ethyl-10-hydroxycamptothecin-glucose conjugates as potential anti-colorectal cancer agents.

7-Ethyl-10-hydroxycamptothecin (SN38), a highly potent metabolite of irinotecan, has an anticancer efficacy 100-1000 folds more than irinotecan in vitro. However, the clinical application of SN38 has been limited due to the very narrow therapeutic window and poor water solubility. Herein, we report the SN38-glucose conjugates (Glu-SN38) that can target cancer cells due to their selective uptake via glucose transporters, which are overexpressed in most cancers. The in vitro antiproliferative activities against human cancer cell lines and normal cells of Glu-SN38 were investigated. One of the conjugates named 5b showed high potency and selectivity against human colorectal cancer cell line HCT116. Furthermore, 5b remarkably inhibited the growth of HCT116 in vivo. These results suggested that 5b could be a promising drug candidate for treating colorectal cancer.

A comprehensive prognostic analysis of osimertinib treatment in advanced non-small cell lung cancer patients with acquired EGFR-T790M mutation: a real-world study.

PURPOSE: Osimertinib is the standard treatment for advanced non-small cell lung cancer (NSCLC) patients with T790M mutation after the failure of first-/second-generation epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKI). We comprehensively analyzed factors that affect the therapeutic efficacy of the osimertinib treatment in NSCLC patients. METHODS: 351 NSCLC patients with T790M mutation receiving osimertinib treatment were included. We investigated the value of different factors in predicting the clinical outcomes of the osimertinib therapy, including progression-free survival (PFS), overall survival (OS) and objective response rate (ORR). Logistic and COX regression were used to identify prognosticators. RESULTS: In osimertinib therapy, EGFR mutation status (19Del/L858R) at initial diagnosis and the therapeutic choice of prior EGFR-TKI agent was not associated with patients' prognosis. Notably, the PFS of the prior EGFR-TKI was independently related to ORR (OR, 95% CI 0.98, 0.96-1.00, p = 0.030), PFS (HR, 95% CI 0.98, 0.97-1.00, p = 0.009) and OS (HR, 95% CI 0.96, 0.93-0.98, p < 0.001) of osimertinib treatment. Among distinct organ metastases, only bone metastasis was related to the efficacy of osimertinib, in terms of ORR (OR, 95% CI 1.97, 1.27-3.06, p = 0.002), PFS (HR, 95% CI 1.55, 1.18-2.03, p = 0.001) and OS (HR, 95% CI 1.81, 1.27-2.59, p = 0.001). However, the therapeutic efficacy of osimertinib was not further impacted by the accumulation of metastatic organs. A performance status score of 2-4 was also an adverse prognosticator for the osimertinib therapy. CONCLUSION: PFS of the prior EGFR-TKI treatment, performance status score and bone metastasis were independent prognosticators of the osimertinib treatment. These findings may facilitate clinicians in the decision-making of osimertinib.

Machine Learning-Based CT Radiomics Analysis for Prognostic Prediction in Metastatic Non-Small Cell Lung Cancer Patients With EGFR-T790M Mutation Receiving Third-Generation EGFR-TKI Osimertinib Treatment.

BACKGROUND AND PURPOSE: As a third-generation EGFR tyrosine kinase inhibitor (TKI), osimertinib is approved for treating advanced non-small cell lung cancer (NSCLC) patients with EGFR-T790M mutation after progression on first- or second-generation EGFR-TKIs such as gefitinib, erlotinib and afatinib. We aim at exploring the feasibility and effectiveness of using radiomic features from chest CT scan to predict the prognosis of metastatic non-small cell lung cancer (NSCLC) patients with EGFR-T790M mutation receiving second-line osimertinib therapy. METHODS: Contrast-enhanced and unenhanced chest CT images before osimertinib treatment were collected from 201 and 273 metastatic NSCLC patients with EGFR-T790M mutation, respectively. Radiomic features were extracted from the volume of interest. LASSO regression was used to preliminarily evaluate the prognostic values of different radiomic features. We then performed machine learning-based analyses including random forest (RF), support vector machine (SVM), stepwise regression (SR) and LASSO regression with 5-fold cross-validation (CV) to establish the optimal radiomic model for predicting the progression-free survival (PFS) of osimertinib treatment. Finally, a combined clinical-radiomic model was developed and validated using the concordance index (C-index), decision-curve analysis (DCA) and calibration curve analysis. RESULTS: Disease progression occurred in 174/273 (63.7%) cases. CT morphological features had no ability in predicting patients' prognosis in osimertinib treatment. Univariate COX regression followed by LASSO regression analyses identified 23 and 6 radiomic features from the contrast-enhanced and unenhanced CT with prognostic value, respectively. The 23 contrast-enhanced radiomic features were further used to construct radiomic models using different machine learning strategies. Radiomic model built by SR exhibited superior predictive accuracy than RF, SVR or LASSO model (mean C-index of the 5-fold CV: 0.660 vs. 0.560 vs. 0.598 vs. 0.590). Adding the SR radiomic model to the clinical model could remarkably strengthen the C-index of the latter from 0.672 to 0.755. DCA and calibration curve analyses also demonstrated good performance of the combined clinical-radiomic model. CONCLUSIONS: Radiomic features extracted from the contrast-enhanced chest CT could be used to evaluate metastatic NSCLC patients' prognosis in osimertinib treatment. Prognostic models combing both radiomic features and clinical factors had a great performance in predicting patients' outcomes.

Radiomic assessment as a method for predicting tumor mutation burden (TMB) of bladder cancer patients: a feasibility study.

BACKGROUND: Tumor mutation burden (TMB) is an emerging prognostic biomarker of immunotherapy for bladder cancer (BLCA). We aim at investigating radiomic features' value in predicting the TMB status of BLCA patients. METHODS: Totally, 75 patients with BLCA were enrolled. Radiomic features extracted from the volume of interest of preoperative pelvic contrast-enhanced computed tomography (CECT) were obtained for each case. Unsupervised hierarchical clustering analysis was performed based on radiomic features. Sequential univariate Logistic regression, the least absolute shrinkage and selection operator (LASSO) regression and the backward stepwise regression were used to develop a TMB-predicting model using radiomic features. RESULTS: The unsupervised clustering analysis divided the total cohort into two groups, i.e., group A (32.0%) and B (68.0%). Patients in group A had a significantly larger proportion of having high TMB against those in group B (66.7% vs. 41.2%, p = 0.039), indicating the intrinsic ability of radiomic features in TMB-predicting. In univariate analysis, 27 radiomic features could predict TMB. Based on six radiomic features selected by logistic and LASSO regression, a TMB-predicting model was built and visualized by nomogram. The area under the ROC curve of the model reached 0.853. Besides, the calibration curve and the decision curve also revealed the good performance of the model. CONCLUSIONS: Our work firstly proved the feasibility of using radiomics to predict TMB for patients with BLCA. The predictive model based on radiomic features from pelvic CECT has a promising ability to predict TMB. Future study with a larger cohort is needed to verify our findings.

The Prognostic Value of Radiomics Features Extracted From Computed Tomography in Patients With Localized Clear Cell Renal Cell Carcinoma After Nephrectomy.

BACKGROUND AND PURPOSE: Radiomics is an emerging field of quantitative imaging. The prognostic value of radiomics analysis in patients with localized clear cell renal cell carcinoma (ccRCC) after nephrectomy remains unknown. METHODS: Computed tomography images of 167 eligible cases were obtained from the Cancer Imaging Archive database. Radiomics features were extracted from the region of interest contoured manually for each patient. Hierarchical clustering was performed to divide patients into distinct groups. Prognostic assessments were performed by Kaplan-Meier curves, COX regression, and least absolute shrinkage and selection operator COX regression. Besides, transcriptome mRNA data were also included in the prognostic analyses. Endpoints were overall survival (OS) and disease-free survival (DFS). Concordance index (C-index), decision curve analysis and calibration curves with 1,000 bootstrapping replications were used for model's validation. RESULTS: Hierarchical clustering groups from nephrographic features and mRNA can divide patients into different prognostic groups while clustering groups from corticomedullary or unenhanced phase couldn't distinguish patients' prognosis. In multivariate analyses, 11 OS-predicting and eight DFS-predicting features were identified in nephrographic phase. Similarly, seven OS-predictors and seven DFS-predictors were confirmed in mRNA data. In contrast, limited prognostic features were found in corticomedullary (two OS-predictor and two DFS-predictors) and unenhanced phase (one OS-predictors and two DFS-predictors). Prognostic models combining both nephrographic features and mRNA showed improved C-index than any model alone (C-index: 0.927 and 0.879 for OS- and DFS-predicting, respectively). In addition, decision curves and calibration curves also revealed the great performance of the novel models. CONCLUSION: We firstly investigated the prognostic significance of preoperative radiomics signatures in ccRCC patients. Radiomics features obtained from nephrographic phase had stronger predictive ability than features from corticomedullary or unenhanced phase. Multi-omics models combining radiomics and transcriptome data could further increase the predictive accuracy.

A novel prognostic model predicting the long-term cancer-specific survival for patients with hypopharyngeal squamous cell carcinoma.

BACKGROUND: Hypopharyngeal squamous cell carcinoma (HSCC) is a rare type of head and neck cancer with poor prognosis. However, till now, there is still no model predicting the survival outcomes for HSCC patients. We aim to develop a novel nomogram predicting the long-term cancer-specific survival (CSS) for patients with HSCC and establish a prognostic classification system. METHODS: Data of 2021 eligible HSCC patients were retrieved from the Surveillance, Epidemiology and End Results database between 2010 and 2015. We randomly split the whole cases (ratio: 7:3) into the training and the validation cohort. Cox regression as well as the Least absolute shrinkage and selection operator (LASSO) COX were used to select significant predictors of CSS. Based on the beta-value of these predictors, a novel nomogram was built. The concordance index (C-index), the calibration curve and the decision curve analysis (DCA) were utilized for the model validation and evaluation using the validation cohort. RESULTS: In total, cancer-specific death occurred in 974/2021 (48.2%) patients. LASSO COX indicated that age, race, T stage, N stage, M stage, surgery, radiotherapy and chemotherapy are significant prognosticators of CSS. A prognostic model based on these factors was constructed and visually presented as nomogram. The C-index of the model was 0.764, indicating great predictive accuracy. Additionally, DCA and calibration curves also demonstrated that the nomogram had good clinical effect and satisfactory consistency between the predictive CSS and actual observation. Furthermore, we developed a prognostic classification system that divides HSCC patients into three groups with different prognosis. The median CSS for HSCC patients in the favorable, intermediate and poor prognosis group was not reached, 39.0-Mo and 10.0-Mo, respectively (p < 0.001). CONCLUSIONS: In this study, we constructed the first nomogram as well as a relevant prognostic classification system that predicts CSS for HSCC patients. We believe these tools would be helpful for clinical practice in patients' consultation and risk group stratification.

Enhancement of the antitumor effect of HER2-directed CAR-T cells through blocking epithelial-mesenchymal transition in tumor cells.

The efficacy of chimeric antigen receptor T (CAR-T) cell therapy in solid tumors is far from satisfactory. In this study, we investigated the influence of epithelial-mesenchymal transition (EMT) on the antitumor effect of CAR-T cells and explored the potential efficacy of combining CAR-T cells with inhibitors targeting EMT. We successfully induced EMT in tumor cells with TGF-ß1, and the antitumor effect of HER2-directed CAR-T cells was significantly suppressed by EMT. Upregulation of PD-L1 was observed in tumor cells undergoing EMT, and change in PD-L1 expression during the EMT process was dependent on the MEK/ERK and PI3K/Akt pathways. Inhibition of the TGF-ß1 pathway could block the EMT process in tumor cells and restore their susceptibility to HER2-directed CAR-T cells in vitro. In addition, targeting the TGF-ß1 pathway significantly enhanced the antitumor effect of HER2-directed CAR-T cells in vivo. Our findings suggest that blocking EMT could potently enhance the antitumor effect of CAR-T cells, which provides a promising approach to improving the therapeutic efficacy of CAR-T cell therapy in solid tumors.

IL-18R-dependent and independent pathways account for IL-18-enhanced antitumor ability of CAR-T cells.

Interleukin-18 (IL-18) has been demonstrated to augment the antitumor capacity of chimeric antigen receptor-T cells (CAR-T) but the underlying mechanisms are largely unknown. Here we explored the effects and mechanisms of exogenous IL-18 on the antitumor response of CAR-T cells. IL-18 boosted the cytotoxicity of human epidermal growth factor receptor-2 (HER2)-specific CAR-T cells ex vivo and enhanced the antitumor efficacy of the CAR-T cells in immunodeficient mice, moreover, IL-18 improved the antitumor capacity of OVA-specific T cells in immunocompetent mice, indicating the universal enhancing function of IL-18 for adoptive cell therapy. To address the roles of IL-18 receptor (IL-18R) in the enhancing function, we evaluated the effects of IL-18R knockout (IL-18R-/-) condition in immunocompetent host and CAR-T cells on the IL-18-enhanced antitumor activities. Interestingly, IL-18 persisted to improve the antitumor ability of IL-18R intact CAR-T cells in IL-18R-/- mice. For IL-18R-/- CAR-T cells, however, IL-18 still holds the enhancing ability to boost the antitumor efficacy in IL-18R-/- mice, albeit the ex vivo tumor-killing ability was lower than that of IL-18R intact CAR-T cells, indicating that IL-18R-independent pathway is involved in the enhancement. Furthermore, tagged IL-18 binded to the membrane of IL-18R-/- splenic and lymph node cells and IL-18R intact and IL-18R-/- CAR-T cells showed distinct transcriptomic profiles when stimulated by IL-18. These data demonstrate that IL-18R-independent pathways contribute to functions of IL-18.

Preclinical Evaluation of Chimeric Antigen Receptor-Modified T Cells Specific to Epithelial Cell Adhesion Molecule for Treating Colorectal Cancer.

Chimeric antigen receptor-modified T cells (CAR-T cells) have emerged as a promising cancer immunotherapy for solid tumors. Epithelial cell adhesion molecule (EpCAM) is overexpressed in a variety of tumors and is recognized as a biomarker for circulating tumor cells and cancer stem cells, representing an attractive target for adoptive T-cell immunotherapy. This study generated third-generation CAR-T cells with redirected specificity to EpCAM (EpCAM CAR-T) by lentiviral vector. The study demonstrated that EpCAM CAR-T cells can elicit lytic cytotoxicity to target cells in an EpCAM-dependent manner and secrete cytotoxic cytokines, including interferon gamma and tumor necrosis factor alpha. Furthermore, adoptive transfer of EpCAM CAR-T cells significantly delayed tumor growth and formation in xenograft models. In addition, the safety evaluation showed that CAR-T cells have no systemic toxicity in mice. The data confirmed the antitumor ability and safety of CAR-T cells targeting EpCAM and may provide a new target for CAR-T cell therapies in treating solid tumors.

Conventional real-time PCR-based detection of T790M using tumor tissue or blood in patients with EGFR TKI-resistant NSCLC.

Blood biopsy has many advantages over tissue biopsy for diagnosing acquired T790M mutation in patients with non-small-cell lung cancer, such as being less risky and painful. New techniques with high sensitivity (eg, droplet digital PCR) show promising results during blood biopsy, but the positive rates of identification are still quite unclear. Whether there are other factors, except technology, affecting the results of blood biopsy is unclear. In this study, we used conventional amplification refractory mutation system to detect tumor tissue or blood for T790M mutation in patients clinically resistant to tyrosine kinase inhibitors. A total of 45 patients treated at West China Hospital between 2014 and 2016 were analyzed. The positive rate of T790M mutation was 70.8% based on tissue biopsy and 37.5% based on blood biopsy. Of the 24 patients whose epidermal growth factor receptor gene was genotyped through tissue and blood biopsy, 10 (41.7%) were concordant for T790M mutation status (κ=0.006). Of the 17 patients positive for T790M by tissue biopsy, 7 (41.2%) were positive for T790M by blood biopsy, and 3 of these 7 were only weakly positive. Of the 7 patients negative for T790M by tissue biopsy, 2 (28.6%) were positive by blood biopsy. Our T790M detection rate is higher than that reported by other studies using digital droplet PCR. These results suggest that other factors (eg, clinical features), intrinsically connected with circulating tumor DNA level, also affect the results of blood biopsy, and thus cannot be controlled through technological optimization.

A retrospective study of pemetrexed combined with oxaliplatin as second-line treatment for advanced non-small-cell lung cancer: Comparable toxicity, better outcome.

BACKGROUND: The outcomes of single-agent regimens as second-line chemotherapy for metastatic non-small-cell lung cancer (NSCLC) are poor. Pemetrexed combined with oxaliplatin has been reportedly well-tolerated and active in chemotherapy-naïve NSCLC. The current study aimed to evaluate the therapeutic effect and toxicity of the regimen of pemetrexed plus oxaliplatin for pretreated advanced NSCLC. PATIENTS AND METHODS: The clinical records of consecutive patients with metastatic NSCLC who received pemetrexed after failed first-line chemotherapy were reviewed. RESULTS: The medical records of 79 eligible patients were examined. Thirty-four of them were treated with a regimen of pemetrexed plus oxaliplatin (PEMOX). Another 45 patients were administered pemetrexed alone (PEM). Both regimens were well-tolerated and there was no therapy-related death. Comparable response rates (15.2% vs. 11.1%) and tumor control rates (63.6% vs. 47.5%) were observed between the two groups. Median time to progression and overall survival of the PEMOX and PEM groups were 18 weeks (95% confidence interval (CI): 13.72-22.28 weeks) versus 13 weeks (95%CI: 12.28-13.72 weeks; P= 0.002), and 31 weeks (95%CI: 15.56-46.44 weeks) versus 21 weeks (95%CI: 18.37-23.63 weeks; P= 0.006), respectively. CONCLUSIONS: The current retrospective study suggests that pemetrexed combined with oxaliplatin as second-line treatment for advanced NSCLC has comparable safety and response with a pemetrexed alone regimen, but better survival.

Vitamin D receptor gene Tru9I polymorphism and risk for incidental sporadic colorectal adenomas.

AIM: Recent laboratory and epidemiological studies suggest that vitamin D is a potential agent for colorectal cancer prevention. Its function is partially mediated by the vitamin D receptor (VDR). The aim of this study was to investigate whether a novel G (allele "U") >A (allele "u") polymorphism (Tru9I) in the VDR intron 8 region is associated with risk for colorectal adenoma in a colonoscopy-based case-control study. METHODS: Genotyping for a total of 391 subjects was carried out through PCR and restriction fragment length polymorphism. RESULTS: The frequencies of "U" and "u" alleles were 89.3% and 10.7%, respectively. The "Uu" and "uu" genotypes were associated with decreased risk for adenoma (OR, 0.71; 95%CI, 0.40-1.25). The inverse association was more pronounced for multiple adenomas and adenomas that were larger had moderate or greater dysplasia, or were sessile: the odds ratios (ORs) were, 0.51 (95%CI, 0.21-1.24), 0.37 (95%CI, 0.11-1.28), 0.68 (95%CI, 0.33-1.41), and 0.36 (95%CI, 0.13-0.97) respectively. In joint/combined analyses, inverse associations were more obvious among those who had at least one "u" allele and also were younger (OR, 0.60; 95%CI, 0.26-1.37), women (OR, 0.38; 95%CI, 0.17-0.88), did not smoke (OR, 0.39; 95%CI, 0.13-1.23), or took NSAID (OR, 0.38; 95%CI, 0.12-1.25), but no evidence existed for interactions with calcium or vitamin D intake. CONCLUSION: Our findings suggest that the VDR Tru9I polymorphism may be associated with lower risk for colorectal adenoma, particularly in interaction with various risk factors, but not with calcium or vitamin D.

Novel genetic variations of the p53R2 gene in patients with colorectal adenoma and controls.

AIM: p53-inducible ribonucleotide reductase small subunit 2 (p53R2) encodes a 351-amino-acid peptide, which catalyzes conversion of ribonucleoside diphosphates to the corresponding deoxyribonucleotides required for DNA replication and repair. A recent study reported that a point mutation (G/T) in the p53 binding sequence in a colon cancer cell line completely impaired p53R2 protein activity. METHODS: We screened the p53R2 gene coding regions and a regulatory region which contains a p53 binding sequence in 100 patients with colorectal adenoma and 100 control subjects using PCR, cold SSCP, and direct DNA sequencing. RESULTS: Although we did not identify genetic variation in all nine exons, four regulatory-region variants were found, of which three were single nucleotide polymorphisms (SNPs) (nt 1 789 C/G, nt 1 928 A/G, 1 933 T/C), and one was 20 bp insertion which replaced a ATTTT between nt 1831 and 1835. Additionally, we determined the frequency of these p53R2 variants in a recently concluded case-control study of incident sporadic colorectal adenomas (163 cases and 210 controls). CONCLUSION: Although more detailed functional characterizations of these polymorphisms remain to be undertaken, these polymorphic sites may be useful for identifying alleles associated with mis-splicing, additional transcript factors and, more generally, in cancer-susceptibility association studies.

[Value of diagnosing micrometastasis by nested RT-PCR in the peripheral blood and bone marrow in non-small cell lung cancer patients].

OBJECTIVE: To evaluate the specificity, sensitivity and their clinical significance of detecting CK19 mRNA expression by nested RT-PCR for molecular diagnosis of micrometastasis in the peripheral blood and bone marrow of patients with non-small cell lung cancer. METHODS: CK19 mRNA expression was detected by nested RT-PCR in peripheral blood and bone marrow samples from 59 lung cancer patients, with samples of 11 benign pulmonary lesion patients and 20 healthy adults as control. RESULTS: The sensitivity of nested RT-PCR was 10(-6). The positive rates of micrometastasis were 33.89% (20/59) in peripheral blood and 22.03% (13/59) in bone marrow, with a highly positive correlation existing between the two groups (P < 0.05). The micrometastasis in peripheral blood and bone marrow was closely correlated with the pathological classification and cell differentiation (P < 0.05) and P-TNM stage (P < 0.01). No CK19 mRNA expression was found in the samples from patients with benign pulmonary lesion or healthy adult volunteers. CONCLUSION: The peripheral blood and bone marrow from patients with non-small cell lung cancer possesses micrometastasis that can not be detected by common methods. Nested RT-PCR technique shows favorable specificity and sensitivity in detecting the condition with definite clinical prospects.