Utilizing dual-responsive iridium(Ⅲ) complex for hepatocellular carcinoma: Integrating photoacoustic imaging with chemotherapy and photodynamic therapy

Stimuli-triggered release and alleviating resistance of iridium(Ⅲ)-based drugs at tumor sites remains challengeable for clinical hepatoma therapy.Herein,a doxorubicin@iridium-transferrin(DOX@Ir-TF)nanovesicle was synthesized by carboxylated-transferrin(TF)and doxorubicin-loaded amphiphilic iridium-amino with quaternary ammonium(QA)groups and disulfide bonds.The QA groups enhanced photophysical properties and broadened production capacity of photoinduced-reactive oxygen species(ROS),while the disulfide-bridged bonds regulated oxidative stress levels through reacting with glutathione(GSH);simultaneously,modification of TF improved recognition and endocytosis of the nanovesicle for tumor cells.Based on in-vitro results,a controlled-release behavior of DOX upon a dualresponsiveness of GSH and near-infrared ray(NIR)irradiation was presented,along with high-efficiency generation of ROS.After an intravenous injection,the nanovesicle was targeted at tumor sites,realizing TF-navigated photoacoustic imaging guidance and synergistic chemotherapy-photodynamic therapy under NIR/GSH stimulations.Overall,newly-synthesized DOX@Ir-TF nanovesicle provided a potential in subcutaneous hepatocellular carcinoma therapy due to integrations of targeting delivery,dual-stimuli responsive release,synergistic therapy strategy,and real-time monitoring.

Oxidative stress-triggered Wnt signaling perturbation characterizes the tipping point of lung adeno-to-squamous transdifferentiation

Lkb1 deficiency confers the Kras-mutant lung cancer with strong plasticity and the potential for adeno-to-squamous transdifferentiation(AST).However,it remains largely unknown how Lkb1 deficiency dynamically regulates AST.Using the classical AST mouse model(Kras LSL-G12D/+;Lkb1flox/flox,KL),we here comprehensively analyze the temporal transcriptomic dynamics of lung tumors at different stages by dynamic network biomarker(DNB)and identify the tipping point at which the Wnt signaling is abruptly suppressed by the excessive accumulation of reactive oxygen species(ROS)through its downstream effector FOXO3A.Bidirectional genetic perturbation of the Wnt pathway using two different Ctnnb1 conditional knockout mouse strains confirms its essential role in the negative regulation of AST.Importantly,pharmacological activation of the Wnt pathway before but not after the tipping point inhibits squamous transdifferentiation,highlighting the irreversibility of AST after crossing the tipping point.Through comparative transcriptomic analyses of mouse and human tumors,we find that the lineage-specific transcription factors(TFs)of adenocarcinoma and squamous cell carcinoma form a“Yin-Yang”counteracting network.Interestingly,inactivation of the Wnt pathway preferentially suppresses the adenomatous lineage TF network and thus disrupts the“Yin-Yang”homeostasis to lean towards the squamous lineage,whereas ectopic expression of NKX2-1,an adenomatous lineage TF,significantly dampens such phenotypic transition accelerated by the Wnt pathway inactivation.The negative correlation between the Wnt pathway and AST is further observed in a large cohort of human lung adenosquamous carcinoma.Collectively,our study identifies the tipping point of AST and highlights an essential role of the ROS-Wnt axis in dynamically orchestrating the homeostasis between adeno-and squamous-specific TF networks at the AST tipping point.

Pathological transition as the arising mechanism for drug resistance in lung cancer

Despite the tremendous efforts for improving therapeutics of lung cancer patients,its prognosis remains disappoint-ing.This can be largely attributed to the lack of comprehensive understanding of drug resistance leading to insuf-ficient development of effective therapeutics in clinic.Based on the current progresses of lung cancer research,we classify drug resistance mechanisms into three different levels:molecular,cellular and pathological level.All these three levels have significantly contributed to the acquisition and evolution of drug resistance in clinic.Our under-standing on drug resistance mechanisms has begun to change the way of clinical practice and improve patient prognosis.In this review,we focus on discussing the pathological changes linking to drug resistance as this has been largely overlooked in the past decades.