Update on Chemoresistance Mechanisms to First-Line Chemotherapy for Gallbladder Cancer and Potential Reversal Strategies.

OBJECTIVE: Gallbladder cancer (GBC) mortality remains high and chemoresistance is increasing. This review consolidates what is known about the mechanisms of chemoresistance to inform and accelerate the development of novel GBC-specific chemotherapies. METHODS: Studies related to GBC-related chemoresistance were systematically screened in PubMed using the advanced search function. Search terms included GBC, chemotherapy, and signaling pathway. RESULTS: Analysis of existing studies showed that GBC has poor sensitivity to cisplatin, gemcitabine (GEM), and 5-fluorouracil. DNA damage repair-related proteins, including CHK1, V-SCR, and H2AX, are involved in tumor adaptation to drugs. GBC-specific chemoresistance is often accompanied by changes in the apoptosis and autophagy-related molecules, BCL-2, CRT, and GBCDRlnc1. CD44 + and CD133 + GBC cells are less resistant to GEM, indicating that tumor stem cells are also involved in chemoresistance. In addition, glucose metabolism, fat synthesis, and glutathione metabolism can influence the development of drug resistance. Finally, chemosensitizers such as lovastatin, tamoxifen, chloroquine, and verapamil are able improve the therapeutic effect of cisplatin or GEM in GBC. CONCLUSIONS: This review summarizes recent experimental and clinical studies of the molecular mechanisms of chemoresistance, including autophagy, DNA damage, tumor stem cells, mitochondrial function, and metabolism, in GBC. Information on potential chemosensitizers is also discussed. The proposed strategies to reverse chemoresistance should inform the clinical use of chemosensitizers and gene-based targeted therapy for this disease.

Andrographolide suppresses breast cancer progression by modulating tumor-associated macrophage polarization through the Wnt/ß-catenin pathway.

Andrographolide(ADE) has been demonstrated to inhibit tumor growth through direct cytotoxicity on tumor cells. However, its potential activity on tumor microenvironment (TME) remains unclear. Tumor-associated macrophages (TAMs), composed mainly of M2 macrophages, are the key cells that create an immunosuppressive TME by secretion of cytokines, thus enhancing tumor progression. Re-polarized subpopulations of macrophages may represent vital new therapeutic alternatives. Our previous studies showed that ADE possessed anti-metastasis and anoikis-sensitization effects. Here, we demonstrated that ADE significantly suppressed M2-like polarization and enhanced M1-like polarization of macrophages. Moreover, ADE inhibited the migration of M2 and tube formation in HUVECs under M2 stimulation. In vivo studies showed that ADE restrained the growth of MDA-MB-231 and HCC1806 human breast tumor xenografts and 4T-1 mammary gland tumors through TAMs. Wnt5a/ß-catenin pathway and MMPs were particularly associated with ADE's regulatory mechanisms to M2 according to RNA-seq and bioinformatics analysis. Moreover， western blot also verified the expressions of these proteins were declined with ADE exposure. Among the cytokines released by M2, PDGF-AA and CCL2 were reduced. Our current findings for the first time elucidated that ADE could modulate macrophage polarization and function through Wnt5a signaling pathway, thereby playing its role in inhibition of triple-negative breast cancer.

OLFM4 depletion sensitizes gallbladder cancer cells to cisplatin through the ARL6IP1/caspase-3 axis.

BACKGROUND: Gallbladder cancer (GBC) is a highly lethal malignancy that carries an extremely poor prognosis due to its chemoresistant nature. Cisplatin (CDDP) is a first-line chemotherapeutic for GBC; however, patients experienced no benefit when treated with CDDP alone. The underlying mechanisms of CDDP resistance in GBC remain largely unknown. METHODS: Agilent mRNA microarray analysis was performed between paired GBC and paracarcinoma to explore differentially expressed genes that might underlie drug resistance. Gene Set Enrichment Analysis (GSEA) was employed to identify key genes mediating CDDP resistance in GBC, and immunohistochemistry was performed to validate protein expression and test correlations with clinicopathological features. In vitro and in vivo functional assays were performed to investigate the proteins' roles in CDDP resistance. RESULTS: Olfactomedin 4 (OLFM4) was differentially expressed between GBC and paracarcinoma and had the highest rank metric score in the GSEA. OLFM4 expression was increasingly upregulated from chronic cholecystitis to GBC in clinical tissue samples, and OLFM4 depletion decreased GBC cell proliferation and invasion. Interestingly, downregulation of OLFM4 reduced ARL6IP1 (antiapoptotic factor) expression and sensitized GBC cells to CDDP both in vitro and in vivo. The evidence indicated that CDDP could significantly increase Bax and Bad expression and activate caspase-3 cascade in OLFM4-depleted GBC cells through ARL6IP1. Clinically, lower OLFM4 expression was associated with good prognosis of GBC patients. CONCLUSIONS: Our results suggest that OLFM4 is an essential gene that contributes to GBC chemoresistance and could serve as a prognostic biomarker for GBC. Importantly, OLFM4 could be a potential chemotherapeutic target.

The prognosis biomarkers based on m6A-related lncRNAs for myeloid leukemia patients.

BACKGROUND: Chronic myeloid leukemia (CML) and acute myeloid leukemia (AML) are two common malignant disorders in leukemia. Although potent drugs are emerging, CML and AML may still relapse after the drug treatment is stopped. N6-methyladenosine (m6A) and lncRNAs play certain roles in the occurrence and development of tumors, but m6A-modified LncRNAs in ML remain to be further investigated. METHODS: In this study, we extracted and analyzed the TCGA gene expression profile of 151 ML patients and the clinical data. On this basis, we then evaluated the immune infiltration capacity of ML and LASSO-penalized Cox analysis was applied to construct the prognostic model based on m6A related lncRNAs to verify the prognostic risk in clinical features of ML. Quantitative reverse transcription PCR was used to detect the expression level of LncRNA in in ML cell lines K562, MOLM13 and acute monocytic leukemia cell line THP-1. RESULTS: We found 70 m6A-related lncRNAs that were related to prognosis, and speculated that the content of stromal cells and immune cells would correlate with the survival of patients with ML. Next, Prognostic risk model of m6A-related lncRNAs was validated to have excellent consistency in clinical features of ML. Finally, we verified the expression levels of CRNDE, CHROMR and NARF-IT1 in ML cell lines K562, MOLM13 and acute monocytic leukemia cell line THP-1, which were significant. CONCLUSIONS: The research provides clues for the prognosis prediction of ML patients by using the m6A-related lncRNAs model we have created, and clarifies the accuracy and authenticity of it.

Umbilical Cord Mesenchymal Stem Cell-Derived Exosomes Ameliorate HaCaT Cell Photo-Aging.

Umbilical cord mesenchymal stem cells (UCMSCs) have been identified as a potentially ideal cell type for use in regenerative therapeutic contexts owing to their excellent paracrine secretory abilities and other desirable properties. Previous work has shown that stem cell-derived exosomes can effectively reduce skin aging, but few studies have specifically focused on the role of UCMSC-derived exosomes in this context. In this study, we isolated exosomes derived from UCMSCs grown in a three-dimensional culture system and explored their ability to modulate the photo-aging of HaCaT keratinocytes. Cell viability and proliferation were assessed using CCK8 assay, whereas wound healing and transwell assays were used to assess cell migratory capabilities. UVB irradiation (60 mJ/cm2) was used to induce photo-aging of HaCaT cells. TUNEL and SA-ß-Gal staining were used to explore HaCaT cell apoptosis and senescence, respectively, whereas real-time quantitative PCR was used to assess the expression of relevant genes at the mRNA level. We found that UCMSC-derived exosomes were able to enhance normal HaCaT cell proliferation and migration while also inhibiting UVB-induced damage to these cells. These exosomes also reduced HaCaT cell apoptosis and senescence, increasing collagen type I expression and reducing matrix metalloproteinase (MMP1) expression in photo-aged HaCaT cells. Together, these findings indicate that UCMSC-derived exosomes have the potential to be used therapeutically to suppress skin aging.

Identification of prognosis-related genes in the cervical cancer immune microenvironment.

BACKGROUND: Cervical cancer is the fourth most commonly diagnosed cancer in women worldwide. The metastasis and invasion of this type of cancer are closely related to the tumor microenvironment. Immune cells and stromal cells dominate the tumor microenvironment in cervical cancer. Therefore, we should further investigate the complex interplay between the tumor progression with immune cells or stromal cells. METHODS: We downloaded the gene expression profiles and clinical data of 307 patients with cervical cancers based on the TCGA database. Subsequently, the Estimation of Stromal and Immune cells in Malignant Tumours using Expression data (ESTIMATE) algorithm was used to calculate the scores of stromal cells and immune cells in order to uncover differential expressed genes, and we analyzed the correlation between their scores and patient survival. Then the Cell type Identification By Estimating Relative Subsets Of known RNA Transcripts (CIBERSORT) deconvolution algorithm was applied to quantify the fraction and infiltration of 22 types of immune cells in cervical cancer. Moreover, we also used R language packs and network tools to analyze GO term, gene enrichment pathway, and protein-protein relationship to trace down genes related to inflammation and immune regulation. RESULTS: The gene expression profiles and corresponding clinical data of 307 patients were obtained from TCGA database. The results showed that the scores were statistically significant between the high immunescore group and the low immunescore group. And the low immunescore group had shorter survival period than the high scores group (P = 0.035). Among the 22 types of immune cells, only T cells and mast cells were significantly related to the survival rate of cervical cancer patients. Moreover, PPI network analysis revealed that CCR5 and CXCL9, -10, -11/CXCR3 axis might be a new target for cervical cancer treatment. Finally, Kaplan-Meier survival curves found outnine representative genes significantly related to survival rate including BTNL8, CCR7, CD1E, CD6, CD27, CD79A, GRAP2, SP1B, LY9. CONCLUSIONS: These genes can be used as markers for the prognosis and diagnosis of cervical cancer and also might be used as treatment targets.

Knockdown of microsomal glutathione S-transferase 1 inhibits lung adenocarcinoma cell proliferation and induces apoptosis.

BACKGROUND: Lung cancer has been the most common cancer worldwide. Microsomal glutathione S-transferase 1 (MGST1) has been reported to play vital roles in oxidative stress, tumor occurrence and drug resistance. However, the biological function and molecular mechanism of MGST1 in lung adenocarcinoma (LUAD) has not yet been elucidated. METHODS: The expression of MGST1 in LUAD tissues and cell lines was evaluated by immunohistochemistry and western blotting, respectively. MGST1 was knocked down by shRNA lentivirus. Cell proliferation was evaluated by MTS, colony formation and EdU assays. Apoptosis was detected by flow cytometry. The potential molecules involved in cell proliferation and apoptosis were examined by western blotting. Finally, the effect of MGST1 on tumor growth in vivo was evaluated in a nude mouse xenograft model. RESULTS: TCGA database analysis and immunohistochemistry demonstrated that MGST1 was highly expressed in LUAD tissues. MGST1 expression in LUAD was correlated with AJCC stage and poor overall survival of patients. MGST1 knockdown significantly inhibited LUAD cell proliferation and induced apoptosis. Mechanistic analyses revealed that MGST1 knockdown might inhibit cell proliferation by inactivating the AKT/GSK-3ß pathway signaling and promote cell apoptosis by regulating the mitochondrial apoptosis pathway related proteins. Moreover, knockdown of MGST1 suppressed tumor growth in vivo. CONCLUSIONS: MGST1 plays an important role in LUAD tumorigenesis and might serve as a potential prognostic factor and therapeutic target in LUAD.

Anticancer effect of the traditional Chinese medicine herb Maytenus compound via the EGFR/PI3K/AKT/GSK3ß pathway.

BACKGROUND: Cancer is a leading cause of death worldwide; folk anticancer medicinal plants have applied for cancer treatment. The Maytenus compound tablet as traditional Chinese compound medicine has been approved for alleviating hyperplasia of mammary glands, whether it can inhibit cancer still unknown. The study was to evaluate the anticancer activity of the Maytenus compound tablet. METHODS: MTS assay evaluated the anti-proliferation effect of the Maytenus compound on H226, A2058, 786O and HeLa cancer cells and two normal epithelial cell lines, namely, 16HBE and Hecate. Nude mouse xenograft tumor model using H226 and HeLa cells examined the drug's anticancer effect in vivo. Western blot assay studied the possible mechanism. RESULTS: The Maytenus compound indicated obvious ability to against proliferation in four strains of cancer cells, particularly against H226 cells by an IC50 of 85.47±10.06 µg/mL and against HeLa cells by an IC50 of 128.74±17.46 µg/mL. However, it had a low cytotoxicity in human normal epithelial cell lines 16HBE with an IC50 of 4,555.86±25.21 µg/mL and Hecate with an IC50 of 833.56±181.88 µg/mL. The Maytenus compound at the 2.45 g/kg oral dosages inhibited the proliferation of H226 cells and HeLa cells in nude mouse with inhibitory rates of 36.06% and 26.45%, respectively, and no organ toxicity. The Maytenus compound could significantly downregulate the expression of pEGFR, pPI3K, pAKT, pGSK3ß, ß-catenin, and c-MYC and upregulate the protein expression of GSK3ß. CONCLUSIONS: The Maytenus compound has significant anticancer activities against human cancer H226 and HeLa cells both in vitro and in vivo, highlighting it may be an anticancer medicine.