Fusobacterium in colonic flora and molecular features of colorectal carcinoma

The CCN axis in cancer development and progression

Since the authors first reviewed this subject in 2016 significant progress has been documented in the CCN field with advances made in the understanding of how members of the CCN family of proteins, CCN1-6, contribute to the pathogenesis and progression, positive and negative, of a larger variety of cancers. As termed matricellular proteins, and more recently the connective communication network, it has become clearer that members of the CCN family interact complexly with other proteins in the extracellular microenvironment, membrane signaling proteins, and can also operate intracellularly at the transcriptional level. In this review we expand on this earlier information providing new detailed information and insights that appropriate a much greater involvement and importance of their role in multiple aspects of cancer. Despite all the new information many more questions have been raised and intriguing results generated that warrant greater investigation. In order to permit the reader to smoothly integrate the new information we discuss all relevant CCN members in the context of cancer subtypes. We have harmonized the nomenclature with CCN numbering for easier comparisons. Finally, we summarize what new has been learned and provide a perspective on how our knowledge about CCN1-6 is being used to drive new initiatives on cancer therapeutics.

Crosstalk Between PD-1/PD-L1 Blockade and Its Combinatorial Therapies in Tumor Immune Microenvironment: A Focus on HNSCC

Head and neck squamous cell carcinoma (HNSCC) is the sixth most common malignancy worldwide with a poor prognosis and high mortality. More than two-thirds of HNSCC patients still have no effective control of clinical progression, and the five-year survival rate is < 50%. Moreover, patients with platinum-refractory HNSCC have a median survival of < 6 months. The significant toxicity and low survival rates of current treatment strategies highlight the necessity for new treatment modalities. Recently, a large number of studies have demonstrated that programmed cell death protein-1 (PD-1) and its ligand, programmed cell death protein ligand-1 (PD-L1) play an essential role in tumor initiation and progression. PD-1/PD-L1 blockade has shown a desired and long-lasting therapeutic effect in the treatment of HNSCC and other malignancies. However, only a small number of patients with HNSCC can benefit from PD-1/PD-L1 blockade monotherapy, while the majority of patients do not respond. To overcome the unsatisfactory therapeutic effect of PD-1/PD-L1 blockade monotherapy, combining other treatment options for HNSCC (including chemotherapy, radiotherapy, targeted therapy, and immunotherapy) in the treatment scheme has become a commonly used strategy. Herein, the potential mechanisms underlying the crosstalk between PD-1/PD-L1 blockade and its combinatorial therapies for HNSCC were reviewed, and it is hoped that the improved understanding of the crosstalk process would provide further ideas for the design of a combinatorial regimen with a higher efficiency and response rate for the treatment of HNSCC and other malignancies.

Targeting Macrophage-Recruiting Chemokines as a Novel Therapeutic Strategy to Prevent the Progression of Solid Tumors

Solid tumors are initiated by genetic mutations in non-hematopoietic cells and progress into invasive malignant tumors. This tumor progression often culminates in metastatic disease that is largely refractory to current therapeutic modalities and thus dramatically reduces survival of tumor patients. As solid tumors account for more than 80% of cancer-related deaths, it is necessary to develop novel therapeutic strategies to treat the diseases. An attractive strategy is to target macrophages in both primary tumors [known as tumor-associated macrophages (TAMs)] and metastatic tumors [called metastasis-associated macrophages (MAMs)]. TAMs and MAMs are abundant in most solid tumors and can promote tumor metastasis. Several studies in various models of solid tumors suggest that the accumulation of TAMs, MAMs, and their progenitor cells is regulated by chemokine ligands released by tumor and stromal cells. Consequently, these macrophage-recruiting chemokines could be potential therapeutic targets to prevent malignant tumor development through disruption of the accumulation of pro-metastatic macrophages. This review will discuss the role of chemokine ligands and their receptors in TAM and MAM accumulation in primary and secondary tumor sites, and finally discuss the therapeutic potential of inhibitors against these macrophage-recruiting chemokines.

Genes encoding membrane proteins showed stable expression in rice under aerobic condition: novel set of reference genes for expression studies

A set of reference genes expressing stably under aerobic and anaerobic conditions in rice is essential to execute omics studies relating to aerobic adaptations. Stability of expression of ten rice reference genes, viz. Actin, eEF-1a, eIF-5C, Exp1, Exp2, Memp, SKP1A, TF-SUI1, TPH, and UBQ5 was validated across six experimental sets in shoot and root tissues at seedling, tillering, and panicle initiation stages. Comprehensively, Memp (Membrane protein), TPH (Tumor protein homolog), and Exp1 (Expressed protein) were revealed as the most stable set with acceptable M and V value according to the gold standards of qRT-PCR using various algorithms/tools. The identified set of reference genes was validated using root trait genes, which showed concurrence with the functional expression patterns in the aerobic and anaerobic adapted cultivars. The Memp (Membrane protein), TPH (Tumor protein homolog), and Exp1 (Expressed protein) genes are the most stable reference genes across the root and shoot at various developmental stages under aerobic and anaerobic conditions in rice. This is the first study for accurate and reliable relative gene expression analysis in rice grown in aerobic and anaerobic conditions.

Cowpea and abiotic stresses: identification of reference genes for transcriptional profiling by qPCR

BACKGROUND

Due to cowpea ability to fix nitrogen in poor soils and relative tolerance to drought and salt stresses, efforts have been directed to identifying genes and pathways that confer stress tolerance in this species. Real-time quantitative PCR (qPCR) has been widely used as the most reliable method to measure gene expression, due to its high accuracy and specificity. In the present study, nine candidate reference genes were rigorously tested for their application in normalization of qPCR data onto roots of four distinct cowpea accessions under two abiotic stresses: root dehydration and salt (NaCl, 100 mM). In addition, the regulation of four target transcripts, under the same referred conditions was also scrutinized.

RESULTS

geNorm, NormFinder, BestKeeper, and ΔCt method results indicated a set of three statistically validated RGs for each stress condition: (I) root dehydration (actin, ubiquitin-conjugating enzyme E2 variant 1D, and a Phaseolus vulgaris unknown gene-UNK), and (II) salt (ubiquitin-conjugating enzyme E2 variant 1D, F-box protein, and UNK). The expression profile of the target transcripts suggests that flavonoids are important players in the cowpea response to the abiotic stresses analyzed, since chalcone isomerase and chalcone synthase were up-regulated in the tolerant and sensitive accessions. A lipid transfer protein also participates in the cowpea tolerance mechanisms to root dehydration and salt stress. The referred transcript was up-regulated in the two tolerant accessions and presented no differential expression in the sensitive counterparts. Chitinase B, in turn, generally related to plant defense, was an important target transcript under salt stress, being up-regulated at the tolerant, and down-regulated in the sensitive accession.

CONCLUSIONS

Reference genes suitable for qPCR analyses in cowpea under root dehydration and salt stress were identified. This action will lead to a more accurate and reliable analysis of gene expression on this species. Additionally, the results obtained in this study may guide future research on gene expression in cowpea under other abiotic stress types that impose osmotic imbalance. The target genes analyzed, in turn, deserve functional evaluation due to their transcriptional regulation under stresses and biotechnological potential.

CpG island methylator phenotype in colorectal cancer

Colorectal cancer (CRC) is one of the most common malignancies worldwide and is caused by accumulation of genetic and epigenetic changes. With the discovery of CpG island methylator phenotype (CIMP), more and more studies have focused on epigenetic modifications in CRC. CIMP is found in a subset of CRC with an exceptionally high frequency of methylated genes. Current research shows that CIMP has several molecular characteristics and is significantly associated with multiple clinicopathological features, but the mechanim of CIMP is still unclear. The prognosis and treatment response in CRC with CIMP are largely different form those of other CRCs, however, the absence of widely accepted CIMP biomarkers has prevented the clinical applications of CIMP to guide the personalized therapy of CRC.