The four and a half LIM domains 1 (FHL1) is considered to play important roles in tumors. This study aims to investigate the role and precise mechanisms of FHL1 in acute myeloid leukemia (AML). Here, we found that FHL1 was highly expressed in AML. CCK8, flow cytometry, and Western blot analysis of cell cycle-related proteins showed that overexpression of FHL1 promoted proliferation and accelerated cell cycle progression in HL-60 cells. Conversely, knockdown of FHL1 inhibited the proliferation and induced cell cycle arrest in KG-1 cells. Furthermore, knockdown of FHL1 promoted cell differentiation, while overexpression of FHL1 restrained all-trans retinoic acid induced cell differentiation in HL-60 cells, revealed by Wright-Giemsa staining and cell surface antigen analysis. Moreover, in vivo experiments revealed that depletion of FHL1 inhibited tumor growth and led to increased levels of CD11b and CD14. Here, we first identify an unexpected and important role of FHL1 that contributes to the AML progression, indicating that FHL1 may be a potential therapeutic target for AML.
Type I Interferons (IFN-I) are important inducers of the antiviral immune response and immune modulators. IFN-β is the most highly expressed IFN-I in the central nervous system (CNS). The infection of SJL mice with the BeAn or the DA strain of Theiler’s murine encephalomyelitis virus (TMEV) results in a progressive demyelinating disease. C57BL/6 mice are usually resistant to TMEV-induced demyelination and eliminate these strains from the CNS within several weeks. Using C57BL/6 IFN-β knockout (IFN-β -/- ) mice infected with TMEV, we evaluated the role of IFN-β in neuroinfection. Despite the resistance of C57BL/6 wild type (WT) mice to TMEV infection, DA-infected IFN-β -/- mice had to be killed at 7 to 8 days post infection (dpi) due to severe clinical disease. In contrast, BeAn-infected IFN-β -/- mice survived until 98 dpi. Nevertheless at 14 dpi, BeAn-infected IFN-β -/- mice showed a stronger encephalitis and astrogliosis, higher viral load as well as higher mRNA levels of Isg15 , Eif2ak2 (PKR), Tnfa , Il1b , Il10 , Il12 and Ifng in the cerebrum than BeAn-infected WT mice. Moreover, the majority of IFN-β -/- mice did not clear the virus from the CNS and developed mild demyelination in the spinal cord at 98 dpi, whereas virus and lesions were absent in the spinal cord of WT mice. Persistently infected IFN-β -/- mice also had higher Isg15 , Eif2ak1 , Tnfa , Il1a , Il1b and Ifng mRNA levels in the spinal cord at 98 dpi than their virus-negative counterparts indicating an activation of IFN-I signaling and ongoing inflammation. Most importantly, BeAn-infected NesCre +/- IFN-β fl/fl mice, which do not express IFN-β in neurons, astrocytes and oligodendrocytes, only developed mild brain lesions similar to WT mice. Consequently, IFN-β produced by neuroectodermal cells does not seem to play a critical role in the resistance of C57BL/6 mice against fatal and demyelinating disease induced by TMEV strains.
Background Topotecan produces DNA damage that induces autophagy in cancer cells. In this study, sensitising topotecan to colon cancer cells with different P53 status via modulation of autophagy was examined. Methodology/Principal Findings The DNA damage induced by topotecan treatment resulted in cytoprotective autophagy in colon cancer cells with wild-type p53. However, in cells with mutant p53 or p53 knockout, treatment with topotecan induced autophagy-associated cell death. In wild-type p53 colon cancer cells, topotecan treatment activated p53, upregulated the expression of sestrin 2, induced the phosphorylation of the AMPKα subunit at Thr172, and inhibited the mTORC1 pathway. Furthermore, the inhibition of autophagy enhanced the anti-tumour effect of topotecan treatment in wild-type p53 colon cancer cells but alleviated the anti-tumour effect of topotecan treatment in p53 knockout cells in vivo. Conclusions/Significance These results imply that the wild-type p53-dependent induction of cytoprotective autophagy is one of the cellular responses that determines the cellular sensitivity to the DNA-damaging drug topotecan. Therefore, our study provides a potential therapeutic strategy that utilises a combination of DNA-damaging agents and autophagy inhibitors for the treatment of colon cancer with wild-type p53.
AbstractSome studies have shown that the change of autophagic capacity may correlate with malignant transformation. Our study was designed to investigate the expression and significance of two autophagy-related proteins, microtubule-associated protein 1 light chain 3 (LC3) and Beclin 1 in the tumorigenesis and development of epithelial ovarian carcinoma. We observed that the positive expression of LC3 and Beclin 1 was significantly higher in the samples of benign and borderline ovarian tumors than those in malignant epithelial ovarian cancers. The expression of LC3 and Beclin 1 was associated with FIGO stage and histological grade. No significant relationship was observed between age and histological grade. However, we observed that the expression of LC3 was not related to Beclin 1. Therefore, the decrease of autophagic capacity may be related to tumorigenesis and development of epithelial ovarian cancer.Addendum: Shen Y, Liang LZ, Hong MH, Xiong Y, Wei M, Zhu XF. Expression and clinical significance of microtubule-associated protein 1 light chain 3 (LC3) and Beclin1 in epithelial ovarian cancer. Ai Zheng 2008; 27:595-9.
The toxicity spectrum between Chinese and Caucasian patients with melanoma who were treated with BRAF inhibitors (BRAFi) may differ. The purpose of the present study was to assess the safety and tolerability of BRAFi and BRAFi-based combination therapies [MEK inhibitors (MEKi) or anti-programmed death-1 (PD-1) antibody] in Chinese patients with BRAF V600E/K mutation-positive metastatic melanoma. We also investigated whether treatment-related adverse events (AEs) correlated with the prognosis. This retrospective study collected data from 43 patients with BRAF V600E/K mutation-positive metastatic melanoma from a single Chinese cancer center. Of the 43 patients, 12 patients received BRAFi monotherapy, 12 patients received BRAFi+MEKi, and 19 patients received BRAFi combined with the anti-PD-1 antibody. The median follow-up time was 19 months. In the BRAFi group, the most common AEs were rashes, palmoplantar erythrodysesthesia, and arthralgia. Four out of 12 (30%) patients experienced grade 3–4 treatment-related AEs. All grades of AEs in the BRAFi+MEKi group were similar to the BRAFi group, except for higher pyrexia (58.3%) and fewer cutaneous AEs. Three out of 12 (25%) patients experienced grade 3–4 AEs, especially pyrexia (16.7%). In the BRAFi+anti-PD-1 antibody group, AEs were similar to the BRAFi group, except for an increased aminotransferase level (36.8%), increased bilirubin (31.6%), and hypothyroidism (15.8%). Eleven out of 19 (57.9%) patients experienced grade 3–4 AEs and four out of 19 (21%) patients discontinued the therapy due to AEs. Treatment-related hepatotoxicity (trHE), defined as an increase in either alanine aminotransferase (ALT), aspartate transaminase (AST), or bilirubin levels, was the only AE identified as a significant poor-prognosis indicator in this study. The median progression-free survival of patients with trHE (41.9%) was 8 months, whereas it was 18 months for those without trHE [ p = 0.046, hazard ratio (HR) = 2.116]. Moreover, this association was independent of medication regimens ( p = 0.014, HR = 2.971). The overall response rate of patients with trHE was significantly lower than those without trHE (44.4 vs. 60.0%, p = 0.024), and we observed a similar trend in patients treated with BRAFi, BRAFi+MEKi, and BRAFi+anti-PD-1 antibody. In conclusion, BRAFi and BRAFi-based combination therapies were tolerable with reversible AEs in Chinese patients with melanoma. The trHE in patients receiving BRAFi and BRAFi-based regimens might indicate a poor therapy-related prognosis.
Tumor suppressor protein P53 induces cycle arrest and apoptosis by mediating the transcriptional expression of its target genes. Mutations causing conformational abnormalities and post-translational modifications that promote degradation are the main reasons for the loss of P53 function in tumor cells. Reporter gene assays that can scientifically reflect the biological function can help discover the mechanism and therapeutic strategies that restore P53 function. In the reporter gene system of this work, tetracycline-inducible expression of wild-type P53 was used to provide a fully activated state as a 100% activity reference for the objective measurement of biological function. It was confirmed by RT-qPCR, cell viability assay, immunofluorescence, and Western blot analysis that the above-mentioned reporter gene system could correctly reflect the differences in biological activity between the wild-type and mutants. After that, the system was tentatively used for related mechanism research and compound activity evaluation. Through the tetracycline-induced co-expression of wild-type P53 and mutant P53 in exact proportion, it was observed that the response modes of typical transcriptional response elements (TREs) to dominant negative P53 mutation effect were not exactly the same. Compared to the relative multiple-to-solvent control, the activity percentage relative to the 100% activity reference of wild-type P53 can better reflect the actual influence of the so-called P53 mutant reactivator. Similarly, relative to the 100% activity reference, it can objectively reflect the biological effects caused by the inhibitor of P53 negative factors, such as MDM2. In conclusion, this study provides a 100% activity reference and a reliable calculation model for relevant basic research and drug development.
Colorectal cancer (CRC) is one of the most lethal and common malignancies in the world. Chemotherapy has been the conventional treatment for metastatic CRC (mCRC) patients. However, the effects of chemotherapy have been unsatisfactory. With the advent of targeted therapy, the survival of patients with CRC have been prolonged. Over the past 20 years, targeted therapy for CRC has achieved substantial progress. However, targeted therapy has the same challenge of drug resistance as chemotherapy. Consequently, exploring the resistance mechanism and finding strategies to address the resistance to targeted therapy, along with searching for novel effective regimens, is a constant challenge in the mCRC treatment, and it is also a hot research topic. In this review, we focus on the current status on resistance to existing targeted therapies in mCRC and discuss future developments.
Abstract Background: Smoking is by far the most important cause of cancer that can be modified at the individual level. Asia has a high incidence of cancer incidence and death, while China has the highest incidence in Asia, and accounting for 27% of the world's cancer deaths. The purpose of the current study was to perform an evidence-based assessment of the burden of tobacco smoking-related cancers death in the Tianjin, China. Methods: A mortality case-control study to assess the risks of all-cause and major causes of cancer death attributable to smoking from 2010 to 2019. Results: Tobacco smoking was responsible for 23,709 (28.87%) cancer deaths among adult men and 8,648 (13.37%) among adult women in 2010 to 2019 in Tianjin. Lung cancer remains the largest cause of cancer death. In men, 49.06% of lung cancer, 27.55% of upper aerodigestive cancer, 10.11% of liver, 13.56% of kidney and other urinary cancer deaths were attributable to tobacco smoking. In women the proportion of ever-smoking-attributable lung cancer was 31.56%, 10.59% of upper aerodigestive and 10.56% of bladder cancer deaths. By year, smoking-attributable cancer deaths in men increased from 1817 in 2010 to 2695 in 2019; for women, the number remained stable at just over 800 per year. Conclusions: Approximately one in three cancer deaths in men and one in six cancer deaths in women would be potentially preventable through appropriate control of tobacco smoking in Tianjin. Effective control programs against tobacco smoking should be further implemented.