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1.
Heliyon ; 9(7): e17714, 2023 Jul.
Article in English | MEDLINE | ID: mdl-37456058

ABSTRACT

More than one half melanoma patients have BRAF gene mutation. BRAF inhibitor vemurafenib is an effective medication for these patients. However, acquired resistance is generally inevitable, the mechanisms of which are not fully understood. Cell senescence and senescence-associated secretory phenotype (SASP) are involved in extensive biological functions. This study was designed to explore the possible role of senescent cells in vemurafenib resistance. The results showed that vemurafenib treatment induced BRAF-mutant but not wild-type melanoma cells into senescence, as manifested by positive ß-galactosidase staining, cell cycle arrest, enlarged cellular morphology, and cyclin D1/p-Rb pathway inhibition. However, the senescent cells induced by vemurafenib (SenV) did not display DNA damage response, p53/p21 pathway activation, reactive oxygen species accumulation, decline of mitochondrial membrane potential, or secretion of canonical SASP cytokines. Instead, SenV released other cytokines, including CCL2, TIMP2, and NGFR, to protect normal melanoma cells from growth inhibition upon vemurafenib treatment. Xenograft experiments further confirmed that vemurafenib induced melanoma cells into senescence in vivo. The results suggest that vemurafenib can induce robust senescence in BRAFV600E melanoma cells, leading to the release of resistance-conferring cytokines. Both the senescent cells and the resistant cytokines could be potential targets for tackling vemurafenib resistance.

2.
Appl Opt ; 61(6): 1323-1330, 2022 Feb 20.
Article in English | MEDLINE | ID: mdl-35201013

ABSTRACT

In some automatic systems, target detection is a common task, and visible images are common sources of raw data. Researchers have confirmed that polarization information highlights manmade targets. We propose an algorithm that fuses polarized and visible images to improve detection accuracy. First, the polarization parameter and visible images are simultaneously converted to the HSV color space. The initial fused image after adjusting the hue and saturation will be transformed into the lab color space. Then, the bisecting k-means algorithm is employed to segment the visible image. The visible and initial images are divided into three types of regions for color transfer in lab color space. Finally, the fused image is transformed back to the RGB color space, and the PolarLITIS data set is applied. The experimental results show that the gradient and contrast of the fused image are improved by 115% and 235.3%, respectively, compared with the visible image, and the final fused image is suitable to view with the naked eye. The proposed algorithm significantly improves accuracy.

4.
Mediators Inflamm ; 2016: 3214105, 2016.
Article in English | MEDLINE | ID: mdl-27247488

ABSTRACT

Epstein-Barr virus-induced gene 3 (EBI3) is a member of the interleukin-12 (IL-12) family structural subunit and can form a heterodimer with IL-27p28 and IL-12p35 subunit to build IL-27 and IL-35, respectively. However, IL-27 stimulates whereas IL-35 inhibits antitumor T cell responses. To date, little is known about the role of EBI3 in tumor microenvironment. In this study, firstly we assessed EBI3, IL-27p28, IL-12p35, gp130, and p-STAT3 expression with clinicopathological parameters of colorectal cancer (CRC) tissues; then we evaluated the antitumor T cell responses and tumor growth with a EBI3 blocking peptide. We found that elevated EBI3 may be associated with IL-12p35, gp130, and p-STAT3 to promote CRC progression. EBI3 blocking peptide promoted antitumor cytotoxic T lymphocyte (CTL) response by inducing Granzyme B, IFN-γ production, and p-STAT3 expression and inhibited CRC cell proliferation and tumor growth to associate with suppressing gp130 and p-STAT3 expression. Taken together, these results suggest that EBI3 may mediate a bidirectional reciprocal-regulation STAT3 signaling pathway to assist the tumor escape immune surveillance in CRC.


Subject(s)
Colorectal Neoplasms/drug therapy , Colorectal Neoplasms/metabolism , Interleukins/metabolism , Minor Histocompatibility Antigens/metabolism , Peptides/therapeutic use , T-Lymphocytes, Cytotoxic/drug effects , T-Lymphocytes, Cytotoxic/metabolism , Adult , Aged , Animals , Blotting, Western , Cell Proliferation/drug effects , Enzyme-Linked Immunosorbent Assay , Female , Flow Cytometry , Humans , Interleukins/antagonists & inhibitors , Male , Mice , Middle Aged , STAT3 Transcription Factor/metabolism , Signal Transduction/drug effects , Tumor Cells, Cultured , Xenograft Model Antitumor Assays
5.
Article in Chinese | MEDLINE | ID: mdl-17971935

ABSTRACT

OBJECTIVE: To investigate the characteristics of circulating type II pre-dendritic cells (pDC2) and evaluate its role in patients with chronic hepatitis B virus infection. METHODS: The quantitative alterations of pDC2 in 27 chronic HBV-infected patients as treated group and 15 healthy individuals as a control group were analyzed by using flow cytometry based on the comparison of CD4+/CD8+ ratios of T lymphocyte subsets between the two groups. The IFN-alpha-producing ability of pDC2 after incubation was determined by ELISA. RESULTS: The percentage of pDC2 (0.096 +/- 0.086) from the peripheral blood in chronic HBV-infected patients were significantly lower than that (0.304 +/- 0.093) from the normal controls (P less than 0.001) while the CD4+/CD8+ ratios were higher than those in normal controls (P less than 0.01). The values of IFN-alpha-producing function and IL-12 of circulating pDC2 in chronic HBV-infected patients group were significantly lower than those in healthy subjects (P < 0.001). The percentage of pDC2 and CD4+/CD8+ ratios were higher in the patients positive for HBV DNA in sera than those in patients negative for HBV DNA in sera (P < 0.01). CONCLUSION: The decreased number of circulating pDC2 and IFN-alpha-producing function from peripheral blood in patients with chronic hepatitis B virus infection may result in the decline of host immune response, which may partially contribute to the disease progress of HBV infection and existence of viral genomic DNA in patient's sera.


Subject(s)
Dendritic Cells/metabolism , Hepatitis B, Chronic/blood , Adolescent , Adult , CD4-CD8 Ratio , Cell Count , DNA, Viral/blood , DNA, Viral/genetics , Dendritic Cells/cytology , Dendritic Cells/immunology , Enzyme-Linked Immunosorbent Assay , Female , Hepatitis B virus/genetics , Hepatitis B virus/growth & development , Hepatitis B, Chronic/immunology , Hepatitis B, Chronic/virology , Humans , Interleukin-12/biosynthesis , Male , Middle Aged , T-Lymphocyte Subsets/cytology , T-Lymphocyte Subsets/immunology , Young Adult
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