Search

Alpinetin (ALP) has been reported to act as an anticancer agent. This study was carried out to elucidate the effect of ALP on high‐fat diet (HFD)‐induced aggressive cancer progression. C57BL/6 mice were fed with a control diet (CD) or HFD and administered with ALP. Following 6 weeks of feeding, mice were inoculated subcutaneously with Lewis lung carcinoma cells (LLC) to develop transplanted lung tumour. ALP suppressed cell proliferation which drives HFD‐induced lung cancer progression. ALP inhibited lipid accumulation in tumour and tumour cells cultured in vitro. qPCR and ELISA analysis of tumour tissues revealed ALP restrained macrophages accumulation, M2s polarization and chemokine secretion. Further, in macrophages cultured in tumour cells conditioned medium (CM), ALP was confirmed to decrease M2s markers expression and chemokine production under high fat. These results demonstrate that ALP suppresses HFD‐promoted harmful changes in tumour microenvironments which are crucial in curbing pulmonary tumour aggravation. [ABSTRACT FROM AUTHOR]

Proto-oncogene non-receptor tyrosine protein kinase c-Src has been involved in the development, progression and metastasis of a variety of human cancers. This protein contains two self-binding peptide (SBP) sites separately between the SH3 domain and polyproline-II (PPII) helix and between the SH2 domain and C-terminal phosphorylatable tail (CTPT), which are potential targets of anticancer drugs to regulate the kinase activity. Here, we described an integrated protocol to systematically investigate the structural basis, energetic property and dynamics behaviour of PPII binding to SH3, and to rationally design potent peptide ligands to target the SBP site of SH3-PPII interaction. Our study found that the PPII peptide is a non-typical binder that can only interact effectively with its cognate SH3 domain when it is integrated into the full-length c-Src kinase protein; stripping the peptide from the protein would considerably impair SH3 affinity by increasing entropy penalty upon the domain-peptide binding, suggesting that the protein context plays an essential role in the SBP’s biological function. Next, we identified that the PPII peptide binds to SH3 domain in a class II manner and, on this basis, we derived a series of modified versions of the wild-type PPII peptide using a structure-based rational strategy. These modified peptide mutants have been structurally optimized with respect to their molecular flexibility and interaction potency with SH3 domain, in order to minimize indirect entropy penalty and to maximize direct binding enthalpy simultaneously. Consequently, several rationally designed peptides were obtained, including PPIIm2 (TSKPQTPGRA), PPIIm5 (KPPTPPRA), PPIIm6 (FPPPPPRA) and PPIIm7 (YPPLPPRA), which exhibit a moderately or considerably increased affinity (Kd = 72, 34, 15 and 5.7 μM, respectively) relative to the wild-type PPII (TSKPQTQGLA) (Kd = 160 μM). These peptides can be used as lead molecular entities to further develop new anticancer therapeutics to regulate c-Src kinase activity by targeting the SBP site of SH3-PPII interaction. [ABSTRACT FROM AUTHOR]

Abstract: Introduction: Radioiodine therapy is commonly used to treat differentiated thyroid cancer (DTC), but a major challenge is dedifferentiation of DTC with the loss of radioiodine uptake. TSHR is a key molecule regulating thyrocyte proliferation and function. This study aimed to test the therapeutic potential of TSHR in dedifferentiated DTC by gene transfection in order to restore cell differentiation and radioiodine uptake. Methods: Dedifferentiated FTC-133 (dFTC-133) cells were obtained by monoclonal culture of FTC-133 cell line after 131I radiation. Recombinant plasmid pcDNA3.1-hTSHR was transfected into dFTC-133 cells by using Lipofectamine 2000 reagent. Immunofluorescence analysis was carried out to confirm TSHR expression and its location. Radioiodine uptake assay was thereafter investigated. mRNAs and proteins of TSHR and other thyroid differentiated markers were detected by real-time PCR and western blot respectively. Results: Among the thyroid specific genes in dFTC-133 cells with stable low radioiodine uptake, TSHR was down-regulated most significantly compared with FTC-133. Then, after TSHR gene transfection, augmented expression of TSHR was observed in dFTC-133 cell surface and cytoplasm by immunofluorescence analysis. It was found that 125I uptake was 2.9 times higher (t =28.63, P <.01) in cells with TSHR transfection than control. The mRNAs of TSHR, NIS, TPO and Tg were also significantly increased by 1.7 times (t =13.8, P <.05), 4 times (t =28.52, P <.05), 1.5 times (t=14.43, P <.05) and 2.2 times (t =19.83, P <.05) respectively compared with control group. Conclusion: Decreased TSHR expression correlated with FTC-133 ongoing dedifferentiation. TSHR transfection contributed to the re-differentiation of dedifferentiated thyroid follicular carcinoma cells. [Copyright &y& Elsevier]

Objective: To construct a new gene therapy plasmid that can express both hepatitis B surface antibody(HBsAb) targeted interferon (dsFvα) and human interleukin 12 (hIL-12) genes for the immunotherapy of chronic hepatitis B., Methods: The pEE14.1-dsFvα plasmid was digested to obtain dsFvα fragment, and then the fragment was cloned into the upstream of IRES sequence in vector pVAX-IRES-hIL-12 digested by the same enzyme to construct the recombinant expression plasmid pVAX-HBVE. The recombinant plasmid was transiently transfected into the HEK293T cells and the expression of target gene was detected by ELISA. The recombinant plasmid pVAX-HBVE was extracted and injected into the leg muscles of HBV transgenic mice with electroporation delivery. The HBV gene copies were detected by quantitative PCR before and after injection., Results: Enzyme digestion and sequencing analysis showed that the recombinant plasmid pVAX-HBVE was constructed as expected before. ELISA showed that dsFvα gene and IL-12 gene were successfully expressed in the supernatant of transfected cells. The recombinant plasmid pVAX-HBVE (30 μg, once) reduced the HBV gene copy by two orders of magnitude after being injected into transgenic mice., Conclusion: The neo-type immune gene therapy plasmid was successfully constructed, which would provide an alternative for immune gene therapy of chronic hepatitis B.