Halofuginone enhances the anti-tumor effect of ALA-PDT by suppressing NRF2 signaling in cSCC

NRF2 inhibitors: Recent progress, future design and therapeutic potential

Nuclear factor erythroid 2-related factor 2 (NRF2) is a crucial transcription factor involved in oxidative stress response, which controls the expression of various cytoprotective genes. Recent research has indicated that constitutively activated NRF2 can enhance patients' resistance to chemotherapy drugs, resulting in unfavorable prognosis. Therefore, the development of NRF2 inhibitors has emerged as a promising approach for overcoming drug resistance in cancer treatment. However, there are limited reports and reviews focusing on NRF2 inhibitors. This review aims to provide a comprehensive analysis of the structure and regulation of the NRF2 signaling pathway, followed by a comprehensive review of reported NRF2 inhibitors. Moreover, the current design strategies and future prospects of NRF2 inhibitors will be discussed, aiming to establish a foundation for the development of more effective NRF2 inhibitors.

Enhancing 5-ALA-PDT efficacy against resistant tumor cells: Strategies and advances

As a precursor of protoporphyrin IX (PpIX), an endogenous pro-apoptotic and fluorescent molecule, 5-Aminolevulinic acid (5-ALA) has gained substantial attention for its potential in fluorescence-guided surgery as well as photodynamic therapy (PDT). Moreover, 5-ALA-PDT has been suggested as a promising chemo-radio sensitization therapy for various cancers. However, insufficient 5-ALA-induced PpIX fluorescence and the induction of multiple resistance mechanisms may hinder the 5-ALA-PDT clinical outcome. Reduced efficacy and resistance to 5-ALA-PDT can result from genomic alterations, tumor heterogeneity, hypoxia, activation of pathways related to cell surveillance, production of nitric oxide, and most importantly, deregulated 5-ALA transporter proteins and heme biosynthesis enzymes. Understanding the resistance regulatory mechanisms of 5-ALA-PDT may allow the development of effective personalized cancer therapy. Here, we described the mechanisms underlying resistance to 5-ALA-PTD across various tumor types and explored potential strategies to overcome this resistance. Furthermore, we discussed future approaches that may enhance the efficacy of treatments using 5-ALA-PDT.

5-aminolevulinic acid photodynamic therapy inhibits the viability, invasion, and migration of cervical cancer SiHa cells by regulating the miR-152-3p/JAK1/STAT1 axis

BACKGROUND

Cervical cancer ranks the fourth most prevalent type of cancer worldwide, characterized by a notably low survival rate, particularly in its metastatic stage. Despite 5-aminolevulinic acid photodynamic therapy (ALA-PDT) demonstrating potential anti-tumor effects against cervical cancer, the intricate mechanisms underlying its efficacy necessitate further investigation. Here, the study aims to elucidate the impact of ALA-PDT on the cancer cell viability, invasion and migration, alongside delineating the underlying molecular mechanisms.

METHODS

Cervical cancer SiHa cells were subjected to ALA and red light irradiation, and we then measured the ALA-PDT's effects on cell functions using various assays. The potential interaction between miR-152-3p and JAK1 was explored through bioinformatics analyses and validated by dual-luciferase reporter assays. Post-transfection with miR-152-3p and JAK1 vectors, cellular functions were re-evaluated. The efficacy of ALA-PDT in tumor suppression was further investigated through tumor transplantation experiment in vivo.

RESULTS

ALA-PDT markedly suppressed SiHa cell viability, invasion and migration, impacting critical markers of proliferation, apoptosis, and epithelial-mesenchymal transition(EMT). And these effects were echoed by the inhibition of miR-152-3p. JAK1 was identified as a direct target of miR-152-3p, and ALA-PDT was found to regulate the expression levels of miR-152-3p, consequently influencing the JAK1/STAT1 signaling pathway. Augmentation of miR-152-3p expression and inhibition of the JAK1/STAT1 pathway mitigated the anti-cancer effects of ALA-PDT, whereas JAK1 overexpression diminished these effects. In vivo analyses demonstrated that ALA-PDT suppressed tumor growth and modulated the miR-152-3p/JAK1/STAT1 pathway expression.

CONCLUSIONS

ALA-PDT inhibits the viability, invasion, and migration of cervical cancer SiHa cells by modulating the miR-152-3p/JAK1/STAT1 axis, offering a promising therapeutic avenue for combating invasive cervical cancer.

5-Aminolevulinic Acid as a Theranostic Agent for Tumor Fluorescence Imaging and Photodynamic Therapy

5-Aminolevulinic acid (ALA) is a naturally occurring amino acid synthesized in all nucleated mammalian cells. As a porphyrin precursor, ALA is metabolized in the heme biosynthetic pathway to produce protoporphyrin IX (PpIX), a fluorophore and photosensitizing agent. ALA administered exogenously bypasses the rate-limit step in the pathway, resulting in PpIX accumulation in tumor tissues. Such tumor-selective PpIX disposition following ALA administration has been exploited for tumor fluorescence diagnosis and photodynamic therapy (PDT) with much success. Five ALA-based drugs have now received worldwide approval and are being used for managing very common human (pre)cancerous diseases such as actinic keratosis and basal cell carcinoma or guiding the surgery of bladder cancer and high-grade gliomas, making it the most successful drug discovery and development endeavor in PDT and photodiagnosis. The potential of ALA-induced PpIX as a fluorescent theranostic agent is, however, yet to be fully fulfilled. In this review, we would like to describe the heme biosynthesis pathway in which PpIX is produced from ALA and its derivatives, summarize current clinical applications of ALA-based drugs, and discuss strategies for enhancing ALA-induced PpIX fluorescence and PDT response. Our goal is two-fold: to highlight the successes of ALA-based drugs in clinical practice, and to stimulate the multidisciplinary collaboration that has brought the current success and will continue to usher in more landmark advances.

Halofuginone ameliorates systemic lupus erythematosus by targeting Blk in myeloid-derived suppressor cells

Systemic lupus erythematosus (SLE) is a multisystemic, inflammatory autoimmune disease. Myeloid-derived suppressor cells (MDSCs) are a heterogeneous population of immature myeloid cells participated in the pathogenesis of SLE. MDSCs has been considered a potential therapeutic target for lupus. As traditional Chinese medicine, Halofuginone (HF) has the extensive immunomodulatory effects on some autoimmune disorders. Our research was dedicated to discovering therapeutic efficacy of HF for lupus to explore novel mechanisms on MDSCs. We found that HF prominently alleviated the systemic symptoms especially nephritis in Imiquimod-induced lupus mice, and simultaneously repaired the immune system, reflected in the alteration of autoantibodies. HF diminished the quantity of MDSCs in lupus mice, and induced apoptosis of MDSCs. Through RNA sequencing performed on the sorted MDSC from lupus mice and HF-treated lupus mice, B lymphoid tyrosine kinase (Blk, a non-receptor cytoplasmic tyrosine kinase) was screened as the target molecule of HF. It's proven that HF had two independent effects on Blk. On the one hand, HF increased the mRNA expression of Blk in MDSCs by inhibiting the nuclear translocation of p65/p50 heterodimer. On the other hand, HF enhanced the kinase activity of Blk in MDSCs through direct molecular binding. We further investigated that Blk suppressed the phosphorylation of downstream ERK signaling pathway to increase the apoptosis of MDSCs. In conclusion, our study illustrated that HF alleviated the disease progression of lupus mice by targeting Blk to promote the apoptosis of MDSCs, which indicated the immunotherapeutic potential of HF to treat lupus.

Targeting oncogenic transcription factors in skin malignancies: An update on cancer stemness and therapeutic outcomes

The skin is the largest organ of the human body and prone to various diseases, including cancer; thus, provides the first line of defense against exogenous biological and non-biological agents. Skin cancer, a complex and heterogenic process, with steep incidence rate often metastasizes due to poor understanding of the underlying mechanisms of pathogenesis and clinical challenges. Indeed, accumulating evidence indicates that deregulation of transcription factors (TFs) due to genetic, epigenetic and signaling distortions plays essential role in the development of cutaneous malignancies and therapeutic challenges including cancer stemness features and reprogramming. This review highlights the recent developments exploring underlying mechanisms how deregulated TFs (e.g., NF-κB, AP-1, STAT etc.,) orchestrates cutaneous onco-pathogenesis, reprogramming, stemness and poor clinical outcomes. Along this line, bioactive drugs, and their derivatives from natural and or synthetic origin has gained attention due to their multitargeting potential, potentially safer and effective therapeutic outcome for human malignancies. We also discussed therapeutic importance of targeting aberrantly expressed TFs in skin cancers with bioactive natural products and or synthetic agents.