Asymmetrically substituted cationic indole- and fluorene porphyrins inhibit tumor proliferation in small intestinal neuroendocrine tumors and medullary thyroid carcinomas

Metabolomic profile of neuroendocrine tumors identifies methionine, porphyrin, and tryptophan metabolisms as key dysregulated pathways associated with patient survival

OBJECTIVE

Metabolic profiling is a valuable tool to characterize tumor biology but remains largely unexplored in neuroendocrine tumors (NETs). Our aim was to comprehensively assess the metabolomic profile of NETs and identify novel prognostic biomarkers and dysregulated molecular pathways.

DESIGN AND METHODS

Multiplatform untargeted metabolomic profiling (GC-MS, CE-MS, and LC-MS) was performed in plasma from 77 patients with G1-2 extra-pancreatic NETs enrolled in the AXINET trial (NCT01744249) (study cohort) and from 68 non-cancer individuals (control). The prognostic value of each differential metabolite (n = 155) in NET patients (P < .05) was analyzed by univariate and multivariate analyses adjusted for multiple testing and other confounding factors. Related pathways were explored by Metabolite Set Enrichment Analysis (MSEA) and Metabolite Pathway Analysis (MPA).

RESULTS

Thirty-four metabolites were significantly associated with progression-free survival (PFS) (n = 16) and/or overall survival (OS) (n = 27). Thirteen metabolites remained significant independent prognostic factors in multivariate analysis, 3 of them with a significant impact on both PFS and OS. Unsupervised clustering of these 3 metabolites stratified patients in 3 distinct prognostic groups (1-year PFS of 71.1%, 47.7%, and 15.4% (P = .012); 5-year OS of 69.7%, 32.5%, and 27.7% (P = .003), respectively). The MSEA and MPA of the 13-metablolite signature identified methionine, porphyrin, and tryptophan metabolisms as the 3 most relevant dysregulated pathways associated with the prognosis of NETs.

CONCLUSIONS

We identified a metabolomic signature that improves prognostic stratification of NET patients beyond classical prognostic factors for clinical decisions. The enriched metabolic pathways identified reveal novel tumor vulnerabilities that may foster the development of new therapeutic strategies for these patients.

Gold(III) porphyrins: Synthesis and interaction with G-quadruplex DNA

G-quadruplex nucleic acids (G4s) are RNA and DNA secondary structures involved in the regulation of multiple key biological processes. They can be found in telomeres, oncogene promoters, RNAs, but also in viral genomes. Due to their unique structural features, very distinct from the canonical duplexes or single-strands, G4s represent promising pharmacological targets for small molecules, namely G4-ligands. Gold(III) penta-cationic porphyrins, as specific G4 ligands, are able to inhibit HIV-1 infectivity and their antiviral activity correlates with their affinity for G4s. Up to now, one of the best antiviral compounds is meso-5,10,15,20-tetrakis[4-(N-methyl-pyridinium-2-yl)phenyl]porphyrinato gold(III) (1). Starting from this compound, we report a structure/affinity relationship study of gold(III) cationic porphyrins to find out the best porphyrin candidate for functionalization, in order to study the antiviral mechanism of action of these gold(III) porphyrins.

Photocytotoxicity, cellular uptake and subcellular localization of amidinophenylporphyrins as potential photodynamic therapeutic agents: An in vitro cell study

The cell-based studies of 5, 10, 15, 20-Tetrakis (4-amidinophenyl) porphyrin (Por1), its Zn complex (Por2) and amidinophenyl bisporphyrin (Por3) were carried out to examine their photocytotoxicity, cellular uptake and sub-cellular localization with human nasopharyngeal carcinoma cell (HK-1), using 5, 10, 15, 20-Tetrakis (N-methyl-4-pyridyl) porphyrin (H2TMPyP) as a reference. These porphyrins showed low dark-cytotoxicity and high photo-cytotoxicity against HK-1. The amphiphilic amidinophenyl bisporphyrin (Por3) displayed better cellular uptake than the single hydrophilic Por1, Por2 and H2TMPyP. As seen from the extent of overlapping of the fluorescence profiles, lysosomal localization of amidinophenylporphyrin Por1-Por3 and mito/lyso localization of the H2TMPyP occurred in the cells. The results suggest these porphyrins with amidine group could be used as potential agents in photodynamic therapy.

Novel 3-substituted fluorine imidazolium/triazolium salt derivatives: synthesis and antitumor activity

A series of novel (±)-3-substituted fluorene–imidazolium/triazolium salt derivatives were synthesized and their antitumor structure–activity relationship studies were reported.

Porphyrins functionalized by quaternary pyridinium units

In this review, free-base and metalloporphyrins, functionalized on meso-positions by quaternary pyridinium units, also referred to as cationic porphyrins, are presented. The article consists of five parts. In the first part free-base porphyrins are described, especially taking account on generation of singlet oxygen; next parts concern metalloporphyrins. The second and third parts deal with zinc and manganese porphyrins, respectively; in the fourth part copper, palladium, and platinum porphyrins are presented. In the fifth part, describing porphyrins with various metal ions an attention is paid to porphyrin metal-organic frameworks (MOFs) and metal-organic materials (MOMs) in which metalloporphyrins are immobilized; syntheses and characterization of obtained products are shown.

CT and enhanced CT in diagnosis of gastrointestinal neuroendocrine carcinomas

OBJECTIVES

To enhance diagnosis of gastrointestinal neuroendocrine carcinomas using CT and contrast-enhanced CT images.

METHODS

A total of 44 patients with gastrointestinal neuroendocrine carcinomas, as confirmed by clinical pathology and immunohistochemistry in the Sixth Affiliated People's Hospital of Shanghai Jiao Tong University Shanghai China, were included in the study. CT and enhanced CT scanning were performed, and the resulting images were reviewed and analyzed.

RESULTS

Twenty-seven males and 17 females were enrolled. Gastrointestinal involvement included the following: 5 cases located in the middle or inferior segment of the esophagus; 5 in the gastric cardia, 15 in the body of stomach, 6 located in the gastric antrum; 5 located in the Vater papilla of the duodenum; and 8 located in the colon. Among the 44 cases 80%-90% of the lesions had homogeneous density. Totally 81.8% (36/44) cases demonstrated homogeneous enhancement in arterial phases, most of the cases (n = 33) moderately or obviously enhanced. Only 17.2% (8/44) cases appeared as heterogeneous enhancement. And 86.4% cases (n = 38) were further enhanced in the venous phase. The CT images also revealed some of the metastases. Some liver metastasis cases have obvious homogeneous enhancement.

CONCLUSIONS

CT and enhanced CT provide useful information regarding gastrointestinal neuroendocrine carcinomas' location, density, enhancement pattern, and some metastasis. These features are helpful to increase the diagnostic accuracy.

Synthesis of ferrocenyl pyrazole-containing chiral aminoethanol derivatives and their inhibition against A549 and H322 lung cancer cells

A series of novel ethyl 3-ferrocenyl-1-(2-hydroxy-3-(phenylamino)propyl)-1H-pyrazole-5-carboxylate derivatives with optical activity (4) was synthesized by microwave-assisted reaction of substituted aniline and ethyl 3-ferrocenyl-1-(oxiran-2-ylmethyl)-1H-pyrazole-5-carboxylate that was prepared from ethyl 3-ferrocenyl-1H-pyrazole-5-carboxylate and (R)- or (S)-oxiran-2-ylmethyl 4-methylbenzenesulfonate. Structures of the compounds were characterized by means of IR, (1)H NMR and mass spectroscopy. Preliminary biological evaluation showed that all of the compounds could suppress the growth of A549 and H322 lung cancer cells. Among all of the tested compounds 4a, 4b and 4d were more effective and might perform their action through cell cycle arrest. Moreover, although the inhibition differences between R and S enantiomers are mostly not so significant, (R)-4b displayed more effective inhibition than (S)-4b.

Polyaspartamide spin probes containing isoindoline nitroxide and porphyrin groups

Water-soluble polyaspartamide isoindoline nitroxides 5-(4′-aminophenyl)-10,15,20-tris (4′-sulfonatophenyl) porphyrin, trisodium salt–poly[α,β- N-(2-hydroxyethyl)-l-aspartamide]–5-carboxy-1,1,3,3-tetramethylisoindolin-2-yloxyl were synthesized by the incorporation of 5-(4′-aminophenyl)-10,15,20-tris(4′-sulfonatophenyl) porphyrin, trisodium salt, as a tumor-targeting group, and 5-carboxy-1,1,3,3-tetramethylisoindolin-2-yloxyl into poly[α,β- N-(2-hydroxyethyl)-l-aspartamide]. These compounds were characterized, and the in vitro properties were evaluated. The polyaspartamide isoindoline nitroxides had higher relaxation effectiveness and had greater toxicity to HeLa cells than that of 5-carboxy-1,1,3,3-tetramethylisoindolin-2-yloxyl. The polyaspartamide isoindoline nitroxides retained similar electrochemical properties and redox reaction mechanisms as the parent nitroxides. The electron paramagnetic resonance spectra of polyaspartamide isoindoline nitroxides exhibited characteristic hyperfine electron paramagnetic resonance spectra of tetramethyl isoindoline nitroxides, with typical nitroxide g-values and nitrogen isotropic hyperfine coupling constants. Therefore, the water-soluble 5-(4′-aminophenyl)-10,15,20-tris(4′-sulfonatophenyl) porphyrin, trisodium salt–poly[α,β- N-(2-hydroxyethyl)-l-aspartamide]–5-carboxy-1,1,3,3-tetramethylisoindolin-2-yloxyl is considered to be a novel potential spin probe for electron paramagnetic resonance.

A water soluble tri-cationic porphyrin-EDTA conjugate induces apoptosis in human neuroendocrine tumor cell lines

In this study, a completely water soluble tri-cationic porphyrin–EDTA conjugate was synthesized. We present data demonstrating the tumoristatic effects of the novel fully water soluble cationic porphyrin TMPy₃PhenEDTA-P-Cl₄ in the dark, in the medullary thyroid carcinoma cell lines MTC-SK and SHER-I and weaker effects in the small intestinal neuroendocrine tumor cell line KRJ-I. In addition, cytotoxic effects were also studied in normal human fibroblasts that represent normal tissue and the results are compared to the tumor cell lines.