Actionable cancer vulnerability due to translational arrest, p53 aggregation and ribosome biogenesis stress evoked by the disulfiram metabolite CuET

Breaking the Chains of Therapeutic Blockade: Pyroptosis-Induced Photothermal-Chemotherapy with Targeted Nanoprobes in Triple-Negative Breast Cancer

There is an important clinical need and social significance, especially for young patients, to explore a new breast-conserving strategy that is not dependent on biomarkers for anti-triple-negative breast cancer. Disulfiram, historically employed for the treatment of chronic alcoholism, has recently emerged as a promising antitumor agent in combination with Cu2+. However, reported disulfiram-Cu2+ codelivery regimens often suffer from instability as well as inadequate drug metabolism, which is detrimental to the production and action of the antitumor active ingredient copper(II) bis(diethyldithiocarbamate). To address this obstacle, this study tested nanosystems ICG-CuET@PLGA-CS-HA (IC@PCH) nanoparticles (NPs) carrying the chemotherapeutic agent copper(II) bis(diethyldithiocarbamate) and photosensitizer indocyanine green for the efficient delivery of antitumor drugs. Benefiting from the involvement of hyaluronic acid, the prepared IC@PCH NPs not only targeted CD44 on the surface of tumor cells but also showed a longer in vivo circulation time. The in vitro and in vivo results demonstrated that IC@PCH NP-mediated photothermal-chemotherapy treatment led to pyroptosis via the NLRP3/caspase-1 classical pathway, which had a significant therapeutic effect on triple-negative breast cancer. In addition, targeting IC@PCH NPs allows photoacoustic-magnetic resonance-fluorescence trimodal imaging, which is capable of detecting more insidious cancer foci and opens up new avenues for precise cancer diagnosis and treatment.

The molecular mechanism and therapeutic landscape of copper and cuproptosis in cancer

Copper, an essential micronutrient, plays significant roles in numerous biological functions. Recent studies have identified imbalances in copper homeostasis across various cancers, along with the emergence of cuproptosis, a novel copper-dependent form of cell death that is crucial for tumor suppression and therapeutic resistance. As a result, manipulating copper levels has garnered increasing interest as an innovative approach to cancer therapy. In this review, we first delineate copper homeostasis at both cellular and systemic levels, clarifying copper's protumorigenic and antitumorigenic functions in cancer. We then outline the key milestones and molecular mechanisms of cuproptosis, including both mitochondria-dependent and independent pathways. Next, we explore the roles of cuproptosis in cancer biology, as well as the interactions mediated by cuproptosis between cancer cells and the immune system. We also summarize emerging therapeutic opportunities targeting copper and discuss the clinical associations of cuproptosis-related genes. Finally, we examine potential biomarkers for cuproptosis and put forward the existing challenges and future prospects for leveraging cuproptosis in cancer therapy. Overall, this review enhances our understanding of the molecular mechanisms and therapeutic landscape of copper and cuproptosis in cancer, highlighting the potential of copper- or cuproptosis-based therapies for cancer treatment.

Disulfiram/copper triggers cGAS-STING innate immunity pathway via ROS-induced DNA damage that potentiates antitumor response to PD-1 checkpoint blockade

Immune checkpoint blockades (ICBs) have emerged as the leading strategy for treating advanced malignancies; however, their clinical efficacy is frequently constrained by primary or acquired resistance. Harnessing innate immune signaling to increase lymphocyte infiltration into tumors has been recognized a promising approach to augment the anti-cancer immune response to ICBs. Disulfiram (DSF), an FDA-approved drug for chronic alcoholism, has shown potent anti-tumor effect, particularly when used in combination with copper (Cu). Here, we demonstrated a combination treatment of DSF and Cu (DSF/Cu) robustly activated cancer cell-intrinsic cGAS-STING-dependent innate immune signaling pathway. Further studies revealed that DSF/Cu caused mitochondrial and nuclear DNA damage and the release of cytosolic dsDNA by inducing excessive reactive oxygen species (ROS) generation, thereby triggering innate immunity and enhancing anti-tumor effects. Moreover, DSF/Cu significantly increased the intratumoral infiltration of CD8+ cytotoxic lymphocytes and natural killer (NK) cells, and potentiated the therapeutic efficacy of PD-1 checkpoint blockade in murine tumor models. Overall, our findings provide a rationale underlying the anti-cancer and immunomodulatory function of DSF/Cu and highlight the potential of repurposing DSF to improve responses to ICBs in cancer patients.

Mechanisms of Copper-Induced Autophagy and Links with Human Diseases

As a structural and catalytic cofactor, copper is involved in many biological pathways and is required for the biochemistry of all living organisms. However, excess intracellular copper can induce cell death due to its potential to catalyze the generation of reactive oxygen species, thus copper homeostasis is strictly regulated. And the deficiency or accumulation of intracellular copper is connected with various pathological conditions. Since the success of platinum-based compounds in the clinical treatment of various types of neoplasias, metal-based drugs have shown encouraging perspectives for drug development. Compared to platinum, copper is an essential intracellular trace element that may have better prospects for drug development than platinum. Recently, the potential therapeutic role of copper-induced autophagy in chronic diseases such as Parkinson's, Wilson's, and cardiovascular disease has already been demonstrated. In brief, copper ions, numerous copper complexes, and copper-based nano-preparations could induce autophagy, a lysosome-dependent process that plays an important role in various human diseases. In this review, we not only focus on the current advances in elucidating the mechanisms of copper or copper-based compounds/preparations on the regulation of autophagy but also outline the association between copper-induced autophagy and human diseases.

Unveiling the molecular profile of a prostate carcinoma: implications for personalized medicine

BACKGROUND

Prostate cancer is the most common diagnosed tumor and the fifth cancer related death among men in Europe. Although several genetic alterations such as ERG-TMPRSS2 fusion, MYC amplification, PTEN deletion and mutations in p53 and BRCA2 genes play a key role in the pathogenesis of prostate cancer, specific gene alteration signature that could distinguish indolent from aggressive prostate cancer or may aid in patient stratification for prognosis and/or clinical management of patients with prostate cancer is still missing. Therefore, here, by a multi-omics approach we describe a prostate cancer carrying the fusion of TMPRSS2 with ERG gene and deletion of 16q chromosome arm.

RESULTS

We have observed deletion of KDM6A gene, which may represent an additional genomic alteration to be considered for patient stratification. The cancer hallmarks gene signatures highlight intriguing molecular aspects that characterize the biology of this tumor by both a high hypoxia and immune infiltration scores. Moreover, our analysis showed a slight increase in the Tumoral Mutational Burden, as well as an over-expression of the immune checkpoints. The omics profiling integrating hypoxia, ROS and the anti-cancer immune response, optimizes therapeutic strategies and advances personalized care for prostate cancer patients.

CONCLUSION

The here data reported can lay the foundation for predicting a poor prognosis for the studied prostate cancer, as well as the possibility of targeted therapies based on the modulation of hypoxia, ROS, and the anti-cancer immune response.

Multifaceted role of GCN2 in tumor adaptation and therapeutic targeting

Tumor cells voraciously consume nutrients from their environment to facilitate rapid proliferation, necessitating effective strategies to manage nutrient scarcity during tumor growth and progression. A pivotal regulatory mechanism in this context is the Integrated Stress Response (ISR), which ensures cellular homeostasis under conditions such as endoplasmic reticulum stress, the unfolded protein response, and nutrient deprivation. Within the ISR framework, the kinase GCN2 is critical, orchestrating a myriad of cellular processes including the inhibition of protein synthesis, the enhancement of amino acid transport, autophagy initiation, and angiogenesis. These processes collectively enable tumor survival and adaptation under nutrient-limited conditions. Furthermore, GCN2-mediated pathways may induce apoptosis, a property exploited by specific therapeutic agents. Leveraging extensive datasets from TCGA, GEO, and GTEx projects, we conducted a pan-cancer analysis to investigate the prognostic significance of GCN2 expression across diverse cancer types. Our analysis indicates that GCN2 expression significantly varies and correlates with both adverse and favorable prognoses depending on the type of cancer, illustrating its complex role in tumorigenesis. Importantly, GCN2 also modulates the tumor immune microenvironment, influencing immune checkpoint expression and the functionality of immune cells, thereby affecting immunotherapy outcomes. This study highlights the potential of targeting GCN2 with specific inhibitors, as evidenced by their efficacy in preclinical models to augment treatment responses and combat resistance in oncology. These findings advocate for a deeper exploration of GCN2's multifaceted roles, which could pave the way for novel targeted therapies in cancer treatment, aiming to improve clinical outcomes.

A novel combination therapy for ER+ breast cancer suppresses drug resistance via an evolutionary double-bind

Chemotherapy remains a commonly used and important treatment option for metastatic breast cancer. A majority of ER+ metastatic breast cancer patients ultimately develop resistance to chemotherapy, resulting in disease progression. We hypothesized that an "evolutionary double-bind", where treatment with one drug improves the response to a different agent, would improve the effectiveness and durability of responses to chemotherapy. This approach exploits vulnerabilities in acquired resistance mechanisms. Evolutionary models can be used in refractory cancer to identify alternative treatment strategies that capitalize on acquired vulnerabilities and resistance traits for improved outcomes. To develop and test these models, ER+ breast cancer cell lineages sensitive and resistant to chemotherapy are grown in spheroids with varied initial population frequencies to measure cross-sensitivity and efficacy of chemotherapy and add-on treatments such as disulfiram combination treatment. Different treatment schedules then assessed the best strategy for reducing the selection of resistant populations. We developed and parameterized a game-theoretic mathematical model from this in vitro experimental data, and used it to predict the existence of a double-bind where selection for resistance to chemotherapy induces sensitivity to disulfiram. The model predicts a dose-dependent re-sensitization (a double-bind) to chemotherapy for monotherapy disulfiram.

Mechanisms of cuproptosis and its relevance to distinct diseases

Copper is a trace element required by the organism, but once the level of copper exceeds the threshold, it becomes toxic and even causes death. The underlying mechanisms of copper-induced death are inconclusive, with different studies showing different opinions on the mechanism of copper-induced death. Multiple investigations have shown that copper induces oxidative stress, endoplasmic reticulum stress, nucleolar stress, and proteasome inhibition, all of which can result in cell death. The latest research elucidates a copper-dependent death and denominates it as cuproptosis. Cuproptosis takes place through the combination of copper and lipoylated proteins of the tricarboxylic acid cycle, triggering agglomeration of lipoylated proteins and loss of iron-sulfur cluster proteins, leading to proteotoxic stress and ultimately death. Given the toxicity and necessity of copper, abnormal levels of copper lead to diseases such as neurological diseases and cancer. The development of cancer has a high demand for copper, neurological diseases involve the change of copper contents and the binding of copper to proteins. There is a close relationship between these two kinds of diseases and copper. Here, we summarize the mechanisms of copper-related death, and the association between copper and diseases, to better figure out the influence of copper in cell death and diseases, thus advancing the clinical remedy of these diseases.

The effect of lipid metabolism on cuproptosis-inducing cancer therapy

Cuproptosis provides a new therapeutic strategy for cancer treatment and is thought to have broad clinical application prospects. Nevertheless, some oncological clinical trials have yet to demonstrate favorable outcomes, highlighting the need for further research into the molecular mechanisms underlying cuproptosis in tumors. Cuproptosis primarily hinges on the intracellular accumulation of copper, with lipid metabolism exerting a profound influence on its course. The interaction between copper metabolism and lipid metabolism is closely related to cuproptosis. Copper imbalance can affect mitochondrial respiration and lipid metabolism changes, while lipid accumulation can promote copper uptake and absorption, and inhibit cuproptosis induced by copper. Anomalies in lipid metabolism can disrupt copper homeostasis within cells, potentially triggering cuproptosis. The interaction between cuproptosis and lipid metabolism regulates the occurrence, development, metastasis, chemotherapy drug resistance, and tumor immunity of cancer. Cuproptosis is a promising new target for cancer treatment. However, the influence of lipid metabolism and other factors should be taken into consideration. This review provides a brief overview of the characteristics of the interaction between cuproptosis and lipid metabolism in cancer and analyses potential strategies of applying cuproptosis for cancer treatment.

Identification of novel dithiocarbamate-copper complexes targeting p97/NPL4 pathway in cancer cells

Dithiocarbamates (DTCs) are simple organic compounds with many applications in industry and medicine. They are potent metal chelators forming complexes with various metal ions, including copper. Recently, bis(diethyldithiocarbamate)-copper complex (CuET) has been identified as a metabolic product of the anti-alcoholic drug Antabuse (disulfiram, DSF), standing behind DSF's reported anticancer activity. Mechanistically, CuET in cells causes aggregation of NPL4 protein, an essential cofactor of the p97 segregase, an integral part of the ubiquitin-proteasome system. The malfunction of p97/NPL4 caused by CuET leads to proteotoxic stress accompanied by heat shock and unfolded protein responses and cancer cell death. However, it is not known whether the NPL4 inhibition is unique for CuET or whether it is shared with other dithiocarbamate-copper complexes. Thus, we tested 20 DTCs-copper complexes in this work for their ability to target and aggregate NPL4 protein. Surprisingly, we have found that certain potency against NPL4 is relatively common for structurally different DTCs-copper complexes, as thirteen compounds scored in the cellular NPL4 aggregation assay. These compounds also shared typical cellular phenotypes reported previously for CuET, including the NPL4/p97 proteins immobilization, accumulation of polyubiquitinated proteins, the unfolded protein, and the heat shock responses. Moreover, the active complexes were also toxic to cancer cells (the most potent in the nanomolar range), and we have found a strong positive correlation between NPL4 aggregation and cytotoxicity, confirming NPL4 as a relevant target. These results show the widespread potency of DTCs-copper complexes to target NPL4 with subsequent induction of lethal proteotoxic stress in cancer cells with implications for drug development.