Conjugation of cRGD peptide to chlorophyll a based photosensitizer (HPPH) alters its pharmacokinetics with enhanced tumor-imaging and photosensitizing (PDT) efficacy.

The α(v)ß(3) integrin receptor plays an important role in human metastasis and tumor-induced angiogenesis. Cyclic Arg-Gly-Asp (cRGD) peptide represents a selective α(v)ß(3) integrin ligand that has been extensively used for research, therapy, and diagnosis of neoangiogenesis. For developing photosensitizers with enhanced PDT efficacy, we here report the synthesis of a series of bifunctional agents in which the 3-(1'-hexyloxyethyl)-3-devinylpyropheophorbide a (HPPH), a chlorophyll-based photosensitizer, was conjugated to cRGD and the related analogues. The cell uptake and in vitro PDT efficacy of the conjugates were studied in α(v)ß(3) integrin overexpressing U87 and 4T1 cell lines whereas the in vivo PDT efficacy and fluorescence-imaging potential of the conjugates were compared with the corresponding nonconjugated photosensitizer HPPH in 4T1 tumors. Compared to HPPH, the HPPH-cRGD conjugate in which the arginine and aspartic acid moieties were available for binding to two subunits of α(v)ß(3) integrin showed faster clearance, enhanced tumor imaging and enhanced PDT efficacy at 2-4 h postinjection. Molecular modeling studies also confirmed that the presence of the HPPH moiety in HPPH-cRGD conjugate does not interfere with specific recognition of cRGD by α(v)ß(3) integrin. Compared to U87 and 4T1 cells the HPPH-cRGD showed significantly low photosensitizing efficacy in A431 (α(v)ß(3) negative) tumor cells, suggesting possible target specificity of the conjugate.

Thyroid-stimulating hormone receptor antibodies during follow-up as remission markers in childhood-onset Graves' disease treated with antithyroid drugs.

Graves' disease is uncommon in children. The remission rate after antithyroid drugs (ATD) therapy is lower than in adults. We evaluated the clinical course of ATD therapy in children with Graves' disease in southern Taiwan to determine whether their biochemical markers could be used to predict remission in these patients. We retrospectively reviewed the clinical data of 53 children diagnosed with Graves' disease between 2009 and 2019. Clinical and biochemical parameters were analyzed for predictors of remission. About three-fourths of the patients were female. Their median age at diagnosis was 13 years. No sex differences were found in most clinical characteristics. There was no correlation between thyroid-stimulating hormone receptor antibody (TRAb) levels at diagnosis and thyroid function or adverse reactions to ATD. Relapse occurred in 62% of patients after discontinuation of first-course ATD therapy. Three variables-good initial response to ATD, a decrease in TRAb levels during the first year after diagnosis, and a decrease in TRAb levels during the second year after diagnosis-were significant predictors of remission for more than 18 months. In conclusion, children with Graves' disease who had early ATD-controlled Graves' disease and decreased TRAb levels during the first 2 years are likely to enter remission for more than 18 months.

Zfra activates memory Hyal-2+ CD3- CD19- spleen cells to block cancer growth, stemness, and metastasis in vivo.

Zfra is a 31-amino-acid zinc finger-like protein, which participates in the tumor necrosis factor signaling. Here, we determined that when nude mice and BALB/c mice were pre-injected with nanogram levels of a synthetic Zfra1-31 or truncated Zfra4-10 peptide via tail veins, these mice became resistant to the growth, metastasis and stemness of melanoma cells, and many malignant cancer cells. The synthetic peptides underwent self-polymerization in phosphate-buffered saline. Alteration of the Ser8 phosphorylation site to Gly8 abolished Zfra aggregation and its-mediated cancer suppression in vivo. Injected Zfra peptide autofluoresced due to polymerization and was trapped mainly in the spleen. Transfer of Zfra-stimulated spleen cells to naïve mice conferred resistance to cancer growth. Zfra-binding cells, designated Hyal-2+ CD3- CD19- Z cells, are approximately 25-30% in the normal spleen, but are significantly downregulated (near 0-3%) in tumor-growing mice. Zfra prevented the loss of Z cells caused by tumors. In vitro stimulation or education of naïve spleen cells with Zfra allowed generation of activated Z cells to confer a memory anticancer response in naïve or cancer-growing mice. In particular, Z cells are abundant in nude and NOD-SCID mice, and can be readily activated by Zfra to mount against cancer growth.

Purpurinimide carbohydrate conjugates: effect of the position of the carbohydrate moiety in photosensitizing efficacy.

A lactose moiety was regioselectively introduced at various positions of N-hexyl-mesopurpurinimide (a class of chlorin containing a fused six-membered imide ring system, lambda(max): 700 nm) to investigate the effect of its presence and position on photosensitizing efficacy. The resulting novel structures produced a significant difference in in vitro and in vivo efficacy. Among the positional isomers in which the lactose moiety was introduced at positions 3, 8, and 12, the 3-lactose purpurin-18-N-hexylimide produced the best efficacy. Compared to these analogues, the lactose moiety joined with an amide bond at position 17(2), and with an N-benzyl group bearing a -C[triple bond]C- linkage at position 13(2) showed reduced in vitro/in vivo photosensitivity. A noticeable difference between lactose conjugates in cell uptake (RIF tumor cells) was observed at 3 and 24 h postincubation. Replacing the lactose (Galbeta1 --> 4Glc) with beta-galactose and glucose moieties at position 3 of purpurinimide produced an increase in both cell uptake and in in vitro efficacy, but with reduced in vivo efficacy. Sites of intracellular localization differed among photosensitizers with and without carbohydrate moieties. Molecular modeling shows favorable interactions of 3- and 12-lactose-purpurinimide analogues with both galectin-1 and galectin-3, but clear contributions were not found for the conjugate containing lactose moiety at position 8. In a comparative ELISA study of the lactose conjugates with free lactose, all carbohydrate-purpurinimides showed binding to both galectins with a significant variation between the batches of galectins.