The cancer stem cell hypothesis posits that cancer stem cells,which are rare among the tumor cell population and share many common properties with normal stem cells,and have been positively identified and successfully isolated from some cancers,are responsible for tumorigenesis and implicated in multistage cancer progression,particularly with respect to metastasis.A better understanding may provide insights into the development of cancer stem cell-targeting therapeutic strategies.The examines what is known regarding cancer stem cells' concept,comparison with normal stem cell,potential origins,assays for isolation and their roles in metastasis.

OBJECTIVETo develop an efficient non-viral gene delivery system in order to transfer CDKN1B gene efficiently into lung and liver carcinoma cells.

METHODSA recombinant plasmid composed of CDKN1B sequence and EYFP as reporter gene was constructed and identified. The recombinant DNA was then formulated the lipids-polycation-DNA complexes(LPDs) with protamine sulfate. Several kinds of lung and liver carcinoma cells were transfected by means of LPDs. The physicochemical properties of LPDs were investigated using PCS method and TEM, respectively. The expression of EYFP in A549 cells was observed under fluorescent microscope and evaluated by flow cytometry analysis. Finally, the production of CDKN1B protein in transfected LLC, Chang and 7721 cells was identified by Western blot analysis.

RESULTSThe average diameter of the LPDs were 167 nm with the polydispersity index of 0.35. The average zeta potential of LPDs was +32.6 mV. LPDs look like a sunken sphere. The fluoresent microscope picture clearly indicated the expression of EYFP in A549 cells. The flow cytometry result showed that the transfection efficiency of LPDs in A549 cells was comparable with that of LipofectAMINE, the positive control. Western blot analysis confirmed the production of CDKN1B protein in LLC, Chang and 7721 cells transfected with LPDs, while no CDKN1B protein was detected in cells transfected with naked DNA.

CONCLUSIONThe construction of the recombinant plasmid is successful. LPDs can deliver the recombinant plasmid to lung carcinoma cells and liver carcinoma cells with high efficiency. Therefore, this kind of gene delivery system has the potential uses for the treatment of lung and liver cancer.

Blotting, Western ; Cell Line ; Cell Line, Tumor ; Cyclin-Dependent Kinase Inhibitor p27 ; genetics ; metabolism ; Flow Cytometry ; Green Fluorescent Proteins ; genetics ; metabolism ; Humans ; Liposomes ; chemistry ; Microscopy, Electron, Transmission ; Microscopy, Fluorescence ; Plasmids ; chemistry ; genetics ; Polyamines ; chemistry ; Protamines ; chemistry ; Transfection ; methods

Objective: Several COVID-19 patients have overlapping comorbidities. The independent role of each component contributing to the risk of COVID-19 is unknown, and how some non-cardiometabolic comorbidities affect the risk of COVID-19 remains unclear. Methods: A retrospective follow-up design was adopted. A total of 1,160 laboratory-confirmed patients were enrolled from nine provinces in China. Data on comorbidities were obtained from the patients' medical records. Multivariable logistic regression models were used to estimate the odds ratio ( Results: Overall, 158 (13.6%) patients were diagnosed with severe illness and 32 (2.7%) had unfavorable outcomes. Hypertension (2.87, 1.30-6.32), type 2 diabetes (T2DM) (3.57, 2.32-5.49), cardiovascular disease (CVD) (3.78, 1.81-7.89), fatty liver disease (7.53, 1.96-28.96), hyperlipidemia (2.15, 1.26-3.67), other lung diseases (6.00, 3.01-11.96), and electrolyte imbalance (10.40, 3.00-26.10) were independently linked to increased odds of being severely ill. T2DM (6.07, 2.89-12.75), CVD (8.47, 6.03-11.89), and electrolyte imbalance (19.44, 11.47-32.96) were also strong predictors of unfavorable outcomes. Women with comorbidities were more likely to have severe disease on admission (5.46, 3.25-9.19), while men with comorbidities were more likely to have unfavorable treatment outcomes (6.58, 1.46-29.64) within two weeks. Conclusion Besides hypertension, diabetes, and CVD, fatty liver disease, hyperlipidemia, other lung diseases, and electrolyte imbalance were independent risk factors for COVID-19 severity and poor treatment outcome. Women with comorbidities were more likely to have severe disease, while men with comorbidities were more likely to have unfavorable treatment outcomes.
Adult ; Aged ; COVID-19/virology* ; China/epidemiology* ; Comorbidity ; Female ; Humans ; Male ; Middle Aged ; Retrospective Studies ; Severity of Illness Index ; Treatment Outcome