The First Structure of an Active Mammalian dCTPase and its Complexes With Substrate Analogs and Products

DCTPP1: A promising target in cancer therapy and prognosis through nucleotide metabolism

Deoxycytidine triphosphate pyrophosphatase 1 (DCTPP1) is an important deoxycytidine triphosphate (dCTP) hydrolase responsible for eliminating noncanonical dCTP and maintaining deoxyribonucleoside triphosphate (dNTP) pool homeostasis. This regulation is vital for proper DNA replication and genome stability. Emerging evidence highlights the considerable role of DCTPP1 in tumor progression, chemotherapy resistance, and prognostic prediction. Consequently, DCTPP1 has emerged as a promising nucleotide metabolism-related target for cancer therapy. In this review, we provide a comprehensive summary of the structural and cellular biological features of DCTPP1, its functions, and its role in cancer. In addition, we discuss recent advancments in small molecules targeting DCTPP1, and propose potential directions for future research.

Ligilactobacillus salivarius Lac45 inhibits MRSA and suppresses inflammation in human keratinocyte

Dysbiosis, an imbalance in skin microflora, is a key contributor to inflammatory skin conditions, including atopic dermatitis (AD), seborrheic dermatitis (SD), and psoriasis. In AD, Staphylococcus aureus colonization of skin lesions is prevalent approximately 70% of cases, with disease severity positively correlating with bacterial presence. Moreover, methicillin-resistant Staphylococcus aureus (MRSA) is found in 10-30% of AD skin lesions, highlighting the need for novel therapeutic strategies that target both microbial imbalance and inflammation. This study evaluates Ligilactobacillus salivarius Lac45 (LS-Lac45), a breast milk-derived bacterial strain, for its antimicrobial and anti-inflammatory potential in dermatology. We assessed its antimicrobial activity against MRSA using an agar disk-diffusion assay and its anti-inflammatory effects in a peptidoglycan (PGN)-induced inflammation model in HaCaT keratinocytes. To elucidate its mechanisms of action, mass spectrometry was used to analyze protein expression changes in LS-Lac45-treated keratinocytes. Our results demonstrate that live LS-Lac45 effectively inhibits MRSA growth. Additionally, heat-killed LS-Lac45 significantly reduces PGN-induced production of pro-inflammatory cytokines IL-6, IL-8, and TNF-α. Proteomic analysis further identifies LS-Lac45-mediated modulation of immune-related proteins, including heat shock protein 60, metallothionein 2A, and antioxidant-1, suggesting a role in inflammatory regulation. These findings highlight LS-Lac45 as a candidate for managing MRSA-associated inflammatory skin conditions, particularly AD. While this study provides key insights into its antimicrobial and immunomodulatory properties, further research is needed to evaluate its probiotic characteristics and clinical applicability in dermatology.

DCTPP1, a reliable Q-biomarker for comprehensive evaluation of the quality of tripterygium glycoside tablets based on chemical references

BACKGROUND

As first-line clinical drugs, tripterygium glycoside tablets (TGTs) often have inconsistent efficacy and toxic side effects, mainly due to inadequate quality control. Therefore, clinically relevant quality standards for TGTs are urgently required.

PURPOSE

Based on chemical substances and considering pharmacological efficacy, we aimed to develop an effective quality evaluation method for TGTs.

METHODS

Representative commercial samples of TGTs were collected from different manufacturers, and qualitative UHPLC/LTQ-Orbitrap-MS and quantitative UHPLC-MS/MS analysis methods were successfully applied to evaluate their quality similarities and differences based on their chemical properties. Then the anti-immunity, anti-inflammatory and antitumor activities of TGTs and related monomers were evaluated using Jurkat, RAW264.7, MIA PaCa-2, and PANC-1 as cellular models. Subsequently, we predicted and verified small molecule-DCTPP1 interactions via molecular docking using the established DCTPP1 enzymatic activity assay. Finally, we performed a gray relational analysis to evaluate the chemical characteristics and biological effects of TGTs produced by different manufacturers.

RESULTS

We collected 24 batches of TGTs (D01-D24) from 5 manufacturers (Co. A, Co. B, Co. C, Co. D, Co. E) for quality evaluation. The chemical composition analysis revealed significant differences in the substance bases of the samples. The D02, D18-D20 samples from Co. B constituted a separate group that differed from other samples, mainly in their absence of diterpenoids and triterpenoids, including triptolide, triptophenolide, and triptonide. In vitro anti-immunity, antitumor and anti-inflammatory tests using the same TGT concentration revealed that, except for D02, D18-D20, the remaining 20 samples exhibited different degrees of anti-immunity, antitumor and anti-inflammatory activity. Our experiments verified that triptolide, triptophenolide, and triptonide were all DCTPP1 inhibitors, and that TGTs generally exhibited DCTPP1 enzyme inhibitory activity. Moreover, the inhibitory activity of D02, D18-D20 samples from Co. B was much lower than that of the other samples, with a nearly tenfold difference in IC50. Further comprehensive analysis revealed a high correlation between DCTPP1 enzyme inhibition activity and the anti-immunity and antitumor and anti-inflammatory activities of these samples.

CONCLUSION

The established DCTPP1 enzymatic activity assay proved suitable for quantitative pharmacological and pharmaceutical analysis to complement the existing quality control system for TGTs and to evaluate their effectiveness.

DCTPP1, an Oncogene Regulated by miR-378a-3p, Promotes Proliferation of Breast Cancer via DNA Repair Signaling Pathway

Breast cancer (BRCA) is one of the most deadly cancers worldwide, with poor survival rates that could be due to its high proliferation. Human all-alpha dCTP pyrophosphatase 1 (DCTPP1) is implicated in numerous diseases, including cancers. However, its role in BRCA is unclear. In this study, we used bioinformatic analyses of the ONCOMINE, UALCAN, and GEPIA databases to determine the expression pattern of DCTPP1 in BRCA. We found that elevated DCTPP1 levels correlate with poor BRCA prognosis. DCTPP1 silencing inhibited BRCA cell proliferation and induced apoptosis in vitro, as well as in vivo. Our data show that this tumorigenic effect depends on DNA repair signaling. Moreover, we found that DCTPP1 is directly modulated by miR-378a-3p, whose downregulation is linked to BRCA progression. Our results showed down-regulation of miR-378a-3p in BRCA. Upregulation of miR-378a-3p, on the other hand, can inhibit BRCA cell growth and proliferation. This study shows that reduced miR-378a-3p level enhances DCTPP1 expression in BRCA, which promotes proliferation by activating DNA repair signaling in BRCA.