Tumor Lymphatic Interactions Induce CXCR2-CXCL5 Axis and Alter Cellular Metabolism and Lymphangiogenic Pathways to Promote Cholangiocarcinoma.

Cholangiocarcinoma (CCA), or cancer of bile duct epithelial cells, is a very aggressive malignancy characterized by early lymphangiogenesis in the tumor microenvironment (TME) and lymph node (LN) metastasis which correlate with adverse patient outcome. However, the specific roles of lymphatic endothelial cells (LECs) that promote LN metastasis remains unexplored. Here we aimed to identify the dynamic molecular crosstalk between LECs and CCA cells that activate tumor-promoting pathways and enhances lymphangiogenic mechanisms. Our studies show that inflamed LECs produced high levels of chemokine CXCL5 that signals through its receptor CXCR2 on CCA cells. The CXCR2-CXCL5 signaling axis in turn activates EMT (epithelial-mesenchymal transition) inducing MMP (matrix metalloproteinase) genes such as GLI, PTCHD, and MMP2 in CCA cells that promote CCA migration and invasion. Further, rate of mitochondrial respiration and glycolysis of CCA cells was significantly upregulated by inflamed LECs and CXCL5 activation, indicating metabolic reprogramming. CXCL5 also induced lactate production, glucose uptake, and mitoROS. CXCL5 also induced LEC tube formation and increased metabolic gene expression in LECs. In vivo studies using CCA orthotopic models confirmed several of these mechanisms. Our data points to a key finding that LECs upregulate critical tumor-promoting pathways in CCA via CXCR2-CXCL5 axis, which further augments CCA metastasis.

CXCL11-CXCR3 Axis Mediates Tumor Lymphatic Cross Talk and Inflammation-Induced Tumor, Promoting Pathways in Head and Neck Cancers.

Tumor metastasis to the draining lymph nodes is critical in patient prognosis and is tightly regulated by molecular interactions mediated by lymphatic endothelial cells (LECs). The underlying mechanisms remain undefined in the head and neck squamous cell carcinomas (HNSCCs). Using HNSCC cells and LECs we determined the mechanisms mediating tumor-lymphatic cross talk. The effects of a pentacyclic triterpenoid, methyl 2-trifluoromethyl-3,11-dioxoolean-1,12-dien-30-oate (CF3DODA-Me), a potent anticancer agent, were studied on cancer-lymphatic interactions. In response to inflammation, LECs induced the chemokine (C-X-C motif) ligand 9/10/11 chemokines with a concomitant increase in the chemokine (C-X-C motif) receptor 3 (CXCR3) in tumor cells. CF3DODA-Me showed antiproliferative effects on tumor cells, altered cellular bioenergetics, suppressed matrix metalloproteinases and chemokine receptors, and the induction of CXCL11-CXCR3 axis and phosphatidylinositol 3-kinase/AKT pathways. Tumor cell migration to LECs was inhibited by blocking CXCL11 whereas recombinant CXCL11 significantly induced tumor migration, epithelial-to-mesenchymal transition, and matrix remodeling. Immunohistochemical analysis of HNSCC tumor arrays showed enhanced expression of CXCR3 and increased lymphatic vessel infiltration. Furthermore, The Cancer Genome Atlas RNA-sequencing data from HNSCC patients also showed a positive correlation between CXCR3 expression and lymphovascular invasion. Collectively, our data suggest a novel mechanism for cross talk between the LECs and HNSCC tumors through the CXCR3-CXCL11 axis and elucidate the role of the triterpenoid CF3DODA-Me in abrogating several of these tumor-promoting pathways.

NMR studies of chromomycins, olivomycins, and their derivatives.

Detailed studies on the 13C and 1H NMR spectra of chromomycins A2 and A3, olivomycins A and B, and their derivatives clarified the assignment of many signals which had been unassigned or erroneously reported in the literatures. The revised assignments for chromomycin A3 and olivomycin A include the assignment of a key 13C signal used to discuss the saccharide linkage in question. Structure analyses based on the revised assignments support the alpha,1----3-bond between components of the disaccharide moiety in the molecules. Some general information useful for structure analysis of saccharides is also reported.

3-Substituent effect and 3-methylene substituent effect on the structure-reactivity relationship of 7 beta-(acylamino)-3-cephem-4-carboxylic acid derivatives studied by carbon-13 and IR spectroscopies.

Relationships between the chemical reactivity of 3-substituted cephalosporins or 3-methylene-substituted cephalosporins and several parameters observed by 13C NMR and IR spectroscopies are described. Among 3-substituted cephalosporins, the values of delta (C-3) and delta (COO) of 13C NMR spectra are correlated with the logarithms of the rate constants for alkaline hydrolysis (log kobsd) when substituents at the 3-position are classified into two groups, i.e., OR substituents and others. Among the 3-methylene-substituted cephalosporins, the difference values of the 13C chemical shifts for C-3 and C-4, delta delta (4-3), are correlated with log kobsd. The beta-lactam vC = O value of the solution IR spectra is a good index for the prediction of a significant change of the beta-lactam reactivity resulting from modification of a 3-substituent or a 3-methylene substituent. From analysis of these observed parameters, both resonance and inductive effects of the substituent at the 3-position were found to affect the chemical reactivity of the beta-lactam ring in cephalosporin, while only the inductive effect of the substituent at the 3'-position was found to affect the beta-lactam reactivity.

Two-dimensional NMR spectroscopy of siomycin A. Proton--carbon-13 chemical shift correlation.

A trial application of a recent two-dimensional nuclear magnetic resonance experiment to the polypeptide antibiotic siomycin A is described. Proton--carbon-13 chemical shift correlation measures the proton and carbon-13 chemical shift for each directly bonded CH group in a molecule, in a single experiment. The resultant map of correlated chemical shifts enables the carbon-13 spectrum to be assigned directly from the known proton shifts, and allows individual proton signals to be identified without problems of overlap. The signal-to-noise ratio available from such techniques should enable their application to aqueous protein solutions using currently available high-field spectrometers.

Structural studies on thiocillins I, II and III (studies on antibiotics from the genus Bacillus XXIX).

Thiocillins I, II and III were compared with micrococcin P1 by analysis of acid hydrolyzates of the native and the reduced antibiotics as well as by means of 1H and 13CNMR spectroscopies. As a result of these studies, the differences of these antibiotics were clarified in their structural units, and the structures of thiocillins I, II and III were assigned on the basis of the proposed structure of micrococcin P1.

Water-soluble siomycin-A derivatives. Preparation, chemical structures and biological properties of half-esters of the peptide antibiotic.

The peptide antibiotic siomycin-A was transformed into half-esters with dicarboxylic acids with the intention of making siomycin-A soluble in water. Sodium salts of the half-esters were also prepared. Some of the salts showed antibacterial activities comparable to siomycin-A against Gram-positive bacteria in vitro and exhibited better therapeutic effects in infected mice than siomycin-A. The chemical structures of siomycin-A hemiadipate-II and -III were elucidated by comparing their 13C and 1H NMR spectra with those of siomycin-A. Their physicochemical properties are described.