Toll‐like receptor‐4 signaling in mantle cell lymphoma

BACKGROUND:

Mantle cell lymphoma (MCL) is an incurable B‐cell malignancy, and patients with this disease have the poorest prognosis among all patients with B‐cell lymphomas. The signaling pathways that trigger MCL escape from immune surveillance are unclear. Because Toll‐like receptors (TLRs) initiate innate and adaptive immune responses against invading pathogens, the authors investigated the impact of TLR signaling in MCL cells.

METHODS:

TLR expression was examined in MCL cell lines and in primary tumors. The examination focused on TLR4 and its ligand lipopolysaccharide (LPS) on MCL cells and their function on MCL proliferation and immune evasion.

RESULTS:

MCL cells expressed multiple TLRs, and TLR4 was among the highest expressed molecules. The activation of TLR4 signaling in MCL cells by LPS induced MCL proliferation and up‐regulated the secretion of cytokines like interleukin‐6 (IL‐6), IL‐10, and vascular endothelial growth factor (VEGF). LPS‐pretreated MCL cells inhibited the proliferation and cytolytic activity of T cells by secreted IL‐10 and VEGF, and neutralizing antibodies against these cytokines restored their functions. Similar results were observed in TLR4‐positive/myeloid differentiation 88 (MyD88)‐positive primary lymphoma cells but not in TLR4‐positive/MyD88‐negative primary lymphoma cells from patients with MCL. Knockdown of TLR4 on MCL cells abrogated the effect of LPS on MCL cells in term of cell growth or secretion of the cytokines and evasion of the immune system.

CONCLUSIONS:

The current results indicated that TLR4 signaling triggers a cascade that leads to MCL growth and evasion from immune surveillance. Thus, TLR4 signaling molecules may be novel therapeutic targets in patients with MCL. Cancer 2013. © 2012 American Cancer Society.     

Study of TLR3, TLR4 and TLR9 in breast carcinomas and their association with metastasis

Background  

Toll-like receptors (TLRs) have garnered an extraordinary amount of interest in cancer research due to their role in tumor progression. By activating the production of several biological factors, TLRs induce type I interferons and other cytokines, which drive an inflammatory response and activate the adaptive immune system. The aim of this study was to investigate the expression and clinical relevance of TLR3, 4 and 9 in breast cancer.     

Effects of alpha fetoprotein on escape of Bel 7402 cells from attack of lymphocytes

Background  

Involvement of AFP against apoptosis of tumor cell has been implicated in its evasion of immune surveillance. However, the molecular events of immune escape mechanisms are still unknown. The major observations reported here relate to a possible mechanism by which heptoloma Bel 7402 cells escape immune surveillance in vitro.     

Toll-Like Receptor (<Emphasis Type="Italic">TLR</Emphasis>) and Nucleosome-binding Oligomerization Domain (<Emphasis Type="Italic">NOD</Emphasis>) gene polymorphisms and endometrial cancer risk

Background  

Endometrial cancer is the most common gynaecological malignancy in women of developed countries. Many risk factors implicated in endometrial cancer trigger inflammatory events; therefore, alterations in immune response may predispose an individual to disease. Toll-like receptors (TLRs) and nucleosome-binding oligomerization domain (NOD) genes are integral to the recognition of pathogens and are highly polymorphic. For these reasons, the aim of the study was to assess the frequency of polymorphic variants in TLR and NOD genes in an Australian endometrial cancer population.     

Epigenetic changes within the promoter region of the <Emphasis Type="Italic">HLA-G</Emphasis> gene in ovarian tumors

Background  

Previous findings have suggested that epigenetic-mediated HLA-G expression in tumor cells may be associated with resistance to host immunosurveillance. To explore the potential role of DNA methylation on HLA-G expression in ovarian cancer, we correlated differences in HLA-G expression with methylation changes within the HLA-G regulatory region in an ovarian cancer cell line treated with 5-aza-deoxycytidine (5-aza-dC) and in malignant and benign ovarian tumor samples and ovarian surface epithelial cells (OSE) isolated from patients with normal ovaries.     

Anti-proliferative effects of <Emphasis Type="Italic">Bifidobacterium adolescentis</Emphasis> SPM0212 extract on human colon cancer cell lines

Background  

Lactic acid bacteria (LAB) are beneficial probiotic organisms that contribute to improved nutrition, microbial balance, and immuno-enhancement of the intestinal tract, as well as anti-tumor activity. The aim of the present work was to study the growth inhibition of tumor cells by butanol extract of Bifidobacterium adolescentis isolated from healthy young Koreans.     

<Emphasis Type="Italic">In vitro</Emphasis> and <Emphasis Type="Italic">in vivo</Emphasis> anticancer properties of a <Emphasis Type="Italic">Calcarea carbonica</Emphasis> derivative complex (M8) treatment in a murine melanoma model

Background  

Melanoma is the most aggressive form of skin cancer and the most rapidly expanding cancer in terms of worldwide incidence. Chemotherapeutic approaches to treat melanoma have had only marginal success. Previous studies in mice demonstrated that a high diluted complex derived from Calcarea carbonica (M8) stimulated the tumoricidal response of activated lymphocytes against B16F10 melanoma cells in vitro.     

O<Superscript><Emphasis Type="Italic">6</Emphasis></Superscript>-<Emphasis Type="Italic">methylguanine-DNA methyltransferase</Emphasis> is downregulated in transformed astrocyte cells: implications for anti-glioma therapies

Background  

A novel alkylating agent, temozolomide, has proven efficacious in the treatment of malignant gliomas. However, expression of O ⁶ -methylguanine-DNA methyltransferase (MGMT) renders glioma cells resistant to the treatment, indicating that identification of mechanisms underlying the gene regulation of MGMT is highly required. Although glioma-derived cell lines have been widely employed to understand such mechanisms, those models harbor numerous unidentified genetic lesions specific for individual cell lines, which complicates the study of specific molecules and pathways.     

Intracellular expression of toll-like receptor 4 in neuroblastoma cells and their unresponsiveness to lipopolysaccharide

Background  

Recently it has been reported that, toll-like receptors (TLRs) are expressed on a series of tumor cells, such as colon cancer, breast cancer, prostate cancer, melanoma and lung cancer. Although some cancer cells like melanoma cells are known to respond to lipopolysaccharide (LPS) via TLR4, not all cancer cells are positive for TLR4. There is little information on the expression and function of TLR4 in neuroblastoma cells. In this study, we investigated the expression of TLR4 in human neuroblastoma NB-1 cell line.     

Histone deacetylase inhibitor vorinostat suppresses the growth of uterine sarcomas <Emphasis Type="Italic">in vitro</Emphasis> and <Emphasis Type="Italic">in vivo</Emphasis>

Background  

Uterine sarcomas are very rare malignancies with no approved chemotherapy protocols. Histone deacetylase (HDAC) inhibitors belong to the most promising groups of compounds for molecular targeting therapy. Here, we described the antitumor effects of suberoylanilide hydroxamic acid (SAHA; vorinostat) on MES-SA uterine sarcoma cells in vitro and in vivo. We investigated effects of vorinostat on growth and colony forming ability by using uterine sarcoma MES-SA cells. We analyzed the influence of vorinostat on expression of different HDACs, p21^WAF1 and activation of apoptosis. Finally, we examined the antitumor effects of vorinostat on uterine sarcoma in vivo.     

EBV-positive Hodgkin lymphoma is associated with suppression of p21<Superscript>cip1/waf1</Superscript> and a worse prognosis

Background  

About 30-50% of Hodgkin lymphomas (HLs) harbor the Epstein-Barr virus (EBV), but the impact of EBV infection on clinical outcomes has been unclear. EBV-encoded small RNAs (EBERs) are presented in all EBV-infected cells, but their functions are still less understood.     

The -786T>C promoter polymorphism of the <Emphasis Type="Italic">NOS3</Emphasis>gene is associated with prostate cancer progression

Background  

There is no biological or epidemiological data on the association between NOS3 promoter polymorphisms and prostate cancer. The polymorphisms in the promoter region of NOS3 gene may be responsible for variations in the plasma NO, which may promote cancer progression by providing a selective growth advantage to tumor cells by angiogenic stimulus and by direct DNA damage.     

Association of <Emphasis Type="Italic">CTLA-4</Emphasis> gene polymorphisms with sporadic breast cancer in Chinese Han population

Background  

The host immunogenetic background plays an important role in the development of breast cancer. Cytotoxic T-lymphocyte antigen-4 (CTLA-4) is a molecule expressed predominantly on activated T cells and is important during the down-regulation of T-cell activation. To evaluate the potential influences of CTLA-4 gene polymorphisms on breast cancer risk, a case-control study was conducted in Han women of Northeast China.     

Analysis of the fecal metagenome in long-term survivors of pancreas cancer

Background

The 5-year overall survival of pancreas adenocarcinoma (PCa) remains less than 10%. Clinical and tumor genomic characteristics have not differentiated PCa long-term survivors (LTSs) from unselected patients. Preclinical studies using fecal transplant experiments from LTSs of PCa have revealed delayed tumor growth through unknown mechanisms involving the fecal microbiota. However, features of the fecal microbiome in patients with long-term survival are not well described.

Methods

In this cross-sectional study, comprehensive shotgun metagenomics was performed on stool from PCa patients with long-term survival (n = 16). LTS was defined as >4 years from pancreatectomy and all therapy without recurrence. LTSs were compared to control patients with PCa who completed pancreatectomy and chemotherapy (n = 8). Stool was sequenced using an Illumina NextSeq500. Statistical analyses were performed in R with MicrobiomeSeq and Phyloseq for comparison of LTSs and controls.

Results

All patients underwent pancreatectomy and chemotherapy before sample donation. The median time from pancreatectomy of 6 years (4–14 years) for LTSs without evidence of disease compared to a median disease-free survival of 1.8 years from pancreatectomy in the control group. No differences were observed in overall microbial diversity for LTSs and controls using Shannon/Simpson indexes. Significant enrichment of species relative abundance was observed in LTSs for the Ruminococacceae family specifically Faecalibacterium prausnitzii species as well as Akkermansia muciniphila species.

Conclusions

Stool from patients cured from PCa has more relative abundance of Faecalibacterium prausnitzii and Akkermansia muciniphila. Additional studies are needed to explore potential mechanisms by which the fecal microbiota may influence survival in PCa.

Plain Language Summary

• Although pancreatic cancer treatments have improved, the number of long-term survivors has remained stagnant with a 5-year overall survival estimate of 9%.
• Emerging evidence suggests that microbes within the gastrointestinal tract can influence cancer response through activation of the immune system.
• In this study, we profiled the stool microbiome in long-term survivors of pancreas cancer and controls.
• Several enriched species previously associated with enhanced tumor immune response were observed including Faecalibacterium prausnitzii and Akkermansia muciniphila.
• These findings warrant additional study assessing mechanisms by which the fecal microbiota may enhance pancreatic cancer immune response.

     

Prodrug converting enzyme gene delivery by <Emphasis Type="Italic">L. monocytogenes</Emphasis>

Background  

Listeria monocytogenes is a highly versatile bacterial carrier system for introducing protein, DNA and RNA into mammalian cells. The delivery of tumor antigens with the help of this carrier into tumor-bearing animals has been successfully carried out previously and it was recently reported that L. monocytogenes is able to colonize and replicate within solid tumors after local or even systemic injection.     

Role of nitric oxide in <Emphasis Type="Italic">Salmonella typhimurium</Emphasis>-mediated cancer cell killing

Background  

Bacterial targeting of tumours is an important anti-cancer strategy. We previously showed that strain SL7838 of Salmonella typhimurium targets and kills cancer cells. Whether NO generation by the bacteria has a role in SL7838 lethality to cancer cells is explored. This bacterium has the mechanism for generating NO, but also for decomposing it.     

<Emphasis Type="Italic">In situ</Emphasis> protein expression in tumour spheres: development of an immunostaining protocol for confocal microscopy

Background  

Multicellular tumour sphere models have been shown to closely mimic phenotype characteristics of in vivo solid tumours, or to allow in vitro propagation of cancer stem cells (CSCs). CSCs are usually characterized by the expression of specific membrane markers using flow cytometry (FC) after enzymatic dissociation. Consequently, the spatial location of positive cells within spheres is not documented. Confocal microscopy is the best technique for the imaging of thick biological specimens after multi-labelling but suffers from poor antibody penetration. Thus, we describe here a new protocol for in situ confocal imaging of protein expression in intact spheroids.