Dorsomorphin attenuates ABCG2-mediated multidrug resistance in colorectal cancer.

Colorectal cancer is a common malignant tumor with high mortality, for which chemotherapy resistance is one of the main reasons. The high expression of ABCG2 in the cancer cells and expulsion of anticancer drugs directly cause multidrug resistance (MDR). Therefore, the development of new ABCG2 inhibitors that block the active causes of MDR may provide a strategy for the treatment of colorectal cancer. In this study, we find that dorsomorphin (also known as compound C or BML-275) potently inhibits the transporter activity of ABCG2, thereby preserving the chemotherapeutic agents mitoxantrone and doxorubicin to antagonize MDR in ABCG2-overexpressing colorectal cancer cells. Additionally, dorsomorphin does not alter ABCG2 protein expression. The results of molecular docking studies show that dorsomorphin is bound stably to the ABCG2-binding pocket, suggesting that dorsomorphin is a potent ABCG2 inhibitor that attenuates ABCG2-mediated MDR in colorectal cancer.

Induction immune-checkpoint inhibitors for resectable oncogene-mutant NSCLC: A multicenter pooled analysis.

Despite limited efficacy of immunotherapy for advanced non-small-cell lung cancer (NSCLC) with driver mutations, whether neoadjuvant immunotherapy could be clinically valuable in those patients warrants further investigation. We utilized 40 oncogene-mutant NSCLC treated with induction immunotherapy from a large consecutive multicenter cohort. Overall response rate was 62.5% while 2 patients had disease progression. Of 39 patients that received surgery, R0 resection rate was 97.4%. The major pathological response (MPR) rate was 37.5% and the pathological complete response (pCR) rate was 12.5%. Pre-treatment PD-L1 expression was not a predictive biomarker in these patients. Median disease-free survival for all oncogenic mutation and EGFR mutation was 28.5 months. Indirect comparison through integrating CTONG1103 cohort showed neoadjuvant immunotherapy plus chemotherapy yielded the most superior efficacy among erlotinib and chemotherapy for resectable EGFR-mutant NSCLC. No MPR patients were identified with neoadjuvant immunotherapy plus chemotherapy for uncommon EGFR insertion or point mutations. Our results indicated the potential clinical feasibility of neoadjuvant immunotherapy for resectable localized oncogene-mutant NSCLC especially for EGFR-mutant NSCLC.

Real-World Scenario of Patients With Lung Cancer Amid the Coronavirus Disease 2019 Pandemic in the People's Republic of China.

INTRODUCTION: The coronavirus disease 2019 (COVID-19) outbreak throughout the world has affected millions of people in many ways, putting a huge burden on the health care system. The ongoing outbreak of this respiratory disease has posed critical challenges to public health, research, and medical communities around the world. This study aimed at evaluating the impact of COVID-19 pandemic on patients with lung cancer in the People's Republic of China. METHODS: We collected data on 397 inpatients from a single center during 4 weeks of the pandemic (2020 group) and that of 2504 inpatients during the same period (4 wk) in the past 5 years (2015-2019 group). A questionnaire was used to investigate the medical demands of 803 patients with lung cancer at 65 hospitals in 20 provinces in the People's Republic of China during the pandemic. We evaluated the incidence data of COVID-19 in Guangdong to analyze the tendency of the pandemic and compared it with inpatient data. RESULTS: The number of hospitalizations and lung cancer-related operations had steadily increased from 2015 to 2019 but reduced by an average of 26.72% (133.8) and 57.18% (45.4) in 2020. The hospital capacity decreased by 28.00% (35 inpatient beds) during the pandemic period of infection with severe acute respiratory syndrome coronavirus 2. The pandemic caused a greater impact on medical work related to lung cancer after the Chinese New Year holiday. Patients were most concerned about long waiting times for outpatient services, inpatient beds, physical examinations, or operations (406; 50.56%); the possibility of infection with the novel coronavirus (359; 44.71%); and the difficulties in getting to a hospital owing to transportation outages (279; 34.74%). Patients in stage I and II revealed having less fear about disease progression (14 [18.18%] and four [14.81%], respectively), had lower proportions of delayed medical arrangement (15 [19.48%] and six [22.22%], respectively), and complained less about complex treatment procedures (12 [15.58%] and five [18.52%], respectively). Patients in the high-infected area (345, 56.74%) complained more frequently about longer booking periods than those in the low-infected area (61, 31.28%). CONCLUSIONS: The treatment of patients with lung cancer has been affected by the pandemic to some extent. We provide suggestions on both clinical diagnosis and treatment strategies for lung cancer to optimize the process, given the urgency of the current circumstances. The demand for medical support among patients with lung cancer or other life-threatening diseases should be given sufficient attention, especially during the current COVID-19 outbreak.

Integrated Exploitation of the Structural Diversity Space of Chemotherapy Drugs to Selectively Inhibit HER2 T798M Mutant in Lung Cancer.

An acquired T798M gatekeeper mutation in human epidermal growth factor receptor 2 (HER2) kinase can cause drug resistance to anti-HER2 chemotherapy drugs in lung cancer. Previously, the reversible pan-kinase inhibitor staurosporine has been found to selectively inhibit the HER2 T798M mutant over wild-type kinase, suggesting that the staurosporine scaffold is potentially to develop mutant-selective inhibitors. Here, we systematically evaluated the chemical space of staurosporine scaffold-based compounds in response to HER2 T798M mutation at structural, energetic and molecular levels by using an integrated analysis strategy. With this strategy, we were able to identify several novel wild-type sparing inhibitors with high or moderate selectivity, which are comparable to or even better than that of the parent compound staurosporine. Molecular modeling and structural analysis revealed that noncovalent contacts can form between the side chain of mutated residue Met798 and selective inhibitor ligands, which may improve the favorable interaction energy between the kinase and inhibitor and reduce the unfavorable desolvation penalty upon the kinase-inhibitor binding.

Promoter methylation of tumor suppressor genes in esophageal squamous cell carcinoma.

Esophageal squamous cell carcinoma (ESCC) is a prevalent and fatal cancer in China and other Asian countries. Epigenetic silencing of key tumor suppressor genes (TSGs) is critical to ESCC initiation and progression. Recently, many novel TSGs silenced by promoter methylation have been identified in ESCC, and these genes further serve as potential tumor markers for high-risk group stratification, early detection, and prognosis prediction. This review summarizes recent discoveries on aberrant promoter methylation of TSGs in ESCC, providing better understanding of the role of disrupted epigenetic regulation in tumorigenesis and insight into diagnostic and prognostic biomarkers for this malignancy.

E-cadherin promotes proliferation of human ovarian cancer cells in vitro via activating MEK/ERK pathway.

AIM: E-cadherin is unusually highly expressed in most ovarian cancers. This study was designed to investigate the roles of E-cadherin in the carcinogenesis and progression of ovarian cancers. METHODS: Human ovarian adenocarcinoma cell line SKOV-3 was examined. E-cadherin gene CDH1 in SKOV-3 cells was knocked down via RNA interference (RNAi), and the resultant variation of biological behavior was observed using CCK-8 and colony formation experiment. E-cadherin-mediated Ca(2+)-dependent cell-cell adhesion was used to study the mechanisms underlying the effects of E-cadherin on the proliferation and survival of SKOV-3 cells. The expression levels of E-cadherin, extracellular signal-related kinase (ERK), phosphorylated ERK (P-ERK) were measured using Western blot assays. RESULTS: Transfection with CDH1-siRNA for 24-96 h significantly suppressed the growth and proliferation of SKOV-3 cells. E-cadherin-mediated calcium-dependent cell-cell adhesion of SKOV-3 cells resulted in a rapid increase of P-ERK, but did not modify the expression of ERK protein. The phosphorylation of ERK in the cells was blocked by pretreatment with the MEK1 specific inhibitor PD98059 (50 µmol/L), but not by the PI3K inhibitor wortmannin (1 µmol/L) or PKA inhibitor H89 (10 µmol/L). CONCLUSION: E-cadherin may function as a tumor proliferation enhancer via activating the MEK/ERK pathway in development of ovarian epithelial cancers.