Degradation of FAK-targeting by proteolytic targeting chimera technology to inhibit the metastasis of hepatocellular carcinoma.

Liver cancer is a prevalent malignant cancer, ranking third in terms of mortality rate. Metastasis and recurrence primarily contribute to the high mortality rate of liver cancer. Hepatocellular carcinoma (HCC) has low expression of focal adhesion kinase (FAK), which increases the risk of metastasis and recurrence. Nevertheless, the efficacy of FAK phosphorylation inhibitors is currently limited. Thus, investigating the mechanisms by which FAK affects HCC metastasis to develop targeted therapies for FAK may present a novel strategy to inhibit HCC metastasis. This study examined the correlation between FAK expression and the prognosis of HCC. Additionally, we explored the impact of FAK degradation on HCC metastasis through wound healing experiments, transwell invasion experiments, and a xenograft tumor model. The expression of proteins related to epithelial-mesenchymal transition (EMT) was measured to elucidate the underlying mechanisms. The results showed that FAK PROTAC can degrade FAK, inhibit the migration and invasion of HCC cells in vitro, and notably decrease the lung metastasis of HCC in vivo. Increased expression of E-cadherin and decreased expression of vimentin indicated that EMT was inhibited. Consequently, degradation of FAK through FAK PROTAC effectively suppressed liver cancer metastasis, holding significant clinical implications for treating liver cancer and developing innovative anti-neoplastic drugs.

Stressed out neutrophils drive metastasis.

Stress hormones can contribute to cancer progression, but how immune cells play a role in this process is unclear. In a recent study in Cancer Cell, He et al. showed that glucocorticoids potentiate metastasis by skewing neutrophils toward pro-tumorigenic functions.

The interaction of platelet-related factors with tumor cells promotes tumor metastasis.

Platelets not only participate in thrombosis and hemostasis but also interact with tumor cells and protect them from mechanical damage caused by hemodynamic shear stress and natural killer cell lysis, thereby promoting their colonization and metastasis to distant organs. Platelets can affect the tumor microenvironment via interactions between platelet-related factors and tumor cells. Metastasis is a key event in cancer-related death and is associated with platelet-related factors in lung, breast, and colorectal cancers. Although the factors that promote platelet expression vary slightly in terms of their type and mode of action, they all contribute to the overall process. Recognizing the correlation and mechanisms between these factors is crucial for studying the colonization of distant target organs and developing targeted therapies for these three types of tumors. This paper reviews studies on major platelet-related factors closely associated with metastasis in lung, breast, and colorectal cancers.

Ovarian tumor cell-derived JAGGED2 promotes omental metastasis through stimulating the Notch signaling pathway in the mesothelial cells.

The primary site of metastasis for epithelial ovarian cancer (EOC) is the peritoneum, and it occurs through a multistep process that begins with adhesive contacts between cancer cells and mesothelial cells. Despite evidence that Notch signaling has a role in ovarian cancer, it is unclear how exactly it contributes to ovarian cancer omental metastasis, as well as the cellular dynamics and intrinsic pathways that drive this tropism. Here we show that tumor cells produced the Notch ligand Jagged2 is a clinically and functionally critical mediator of ovarian cancer omental metastasis by activating the Notch signaling in single-layered omental mesothelial cells. In turn, Jagged2 promotes tumor growth and therapeutic resistance by stimulating IL-6 release from mesothelial cells. Additionally, Jagged2 is a potent downstream mediator of the omental metastasis cytokine TGF-ß that is released during omental destruction. Importantly, therapeutic inhibition of Jagged2-mediated omental metastasis was significantly improved by directly disrupting the Notch pathway in omental mesothelial cells. These findings highlight the key role of Jagged2 to the functional interplay between the TGF-ß and the Notch signaling pathways during the metastatic process of ovarian cancer cells to the omentum and identify the Notch signaling molecule as a precision therapeutic target for ovarian cancer metastasis.

Cell surface patching via CXCR4-targeted nanothreads for cancer metastasis inhibition.

The binding of therapeutic antagonists to their receptors often fail to translate into adequate manipulation of downstream pathways. To fix this 'bug', here we report a strategy that stitches cell surface 'patches' to promote receptor clustering, thereby synchronizing subsequent mechano-transduction. The "patches" are sewn with two interactable nanothreads. In sequence, Nanothread-1 strings together adjacent receptors while presenting decoy receptors. Nanothread-2 then targets these decoys multivalently, intertwining with Nanothread-1 into a coiled-coil supramolecular network. This stepwise actuation clusters an extensive vicinity of receptors, integrating mechano-transduction to disrupt signal transmission. When applied to antagonize chemokine receptors CXCR4 expressed in metastatic breast cancer of female mice, this strategy elicits and consolidates multiple events, including interception of metastatic cascade, reversal of immunosuppression, and potentiation of photodynamic immunotherapy, reducing the metastatic burden. Collectively, our work provides a generalizable tool to spatially rearrange cell-surface receptors to improve therapeutic outcomes.

Arenobufagin inhibits lung metastasis of colorectal cancer by targeting c-MYC/Nrf2 axis.

BACKGROUND: Colorectal cancer (CRC) is one of the commonest cancers worldwide. Metastasis is the most common cause of death in patients with CRC. Arenobufagin is an active component of bufadienolides, extracted from toad skin and parotid venom. Arenobufagin reportedly inhibits epithelial-to-mesenchymal transition (EMT) and metastasis in various cancers. However, the mechanism through which arenobufagin inhibits CRC metastasis remains unclear. PURPOSE: This study aimed to elucidate the molecular mechanisms by which arenobufagin inhibits CRC metastasis. METHODS: Wound-healing and transwell assays were used to assess the migration and invasion of CRC cells. The expression of nuclear factor erythroid-2-related factor 2 (Nrf2) in the CRC tissues was assessed using immunohistochemistry. The protein expression levels of c-MYC and Nrf2 were detected by immunoblotting. A mouse model of lung metastasis was used to study the effects of arenobufagin on CRC lung metastasis in vivo. RESULTS: Arenobufagin observably inhibited the migration and invasion of CRC cells by downregulating c-MYC and inactivating the Nrf2 signaling pathway. Pretreatment with the Nrf2 inhibitor brusatol markedly enhanced arenobufagin-mediated inhibition of migration and invasion, whereas pretreatment with the Nrf2 agonist tert­butylhydroquinone significantly attenuated arenobufagin-mediated inhibition of migration and invasion of CRC cells. Furthermore, Nrf2 knockdown with short hairpin RNA enhanced the arenobufagin-induced inhibition of the migration and invasion of CRC cells. Importantly, c-MYC acts as an upstream modulator of Nrf2 in CRC cells. c-MYC knockdown markedly enhanced arenobufagin-mediated inhibition of the Nrf2 signaling pathway, cell migration, and invasion. Arenobufagin inhibited CRC lung metastasis in vivo. Together, these findings provide evidence that interruption of the c-MYC/Nrf2 signaling pathway is crucial for arenobufagin-inhibited cell metastasis in CRC. CONCLUSIONS: Collectively, our findings show that arenobufagin could be used as a potential anticancer agent against CRC metastasis. The arenobufagin-targeted c-MYC/Nrf2 signaling pathway may be a novel chemotherapeutic strategy for treating CRC.

Molecular perspectives on systemic priming and concomitant immunity in colorectal carcinoma.

The progression of metastasis, a complex systemic disease, is facilitated by interactions between tumor cells and their isolated microenvironments. Over the past few decades, researchers have investigated the metastatic spread of cancer extensively, identifying multiple stages in the process, such as intravasation, extravasation, tumor latency, and the development of micrometastasis and macrometastasis. The premetastatic niche is established in target organs by the accumulation of aberrant immune cells and extracellular matrix proteins. The "seed and soil" idea, which has become widely known and accepted, is being used to this day to guide cancer studies. Changes in the local and systemic immune systems have a major impact on whether an infection spreads or not. The belief that the immune response may play a role in slowing tumor growth and may be beneficial against the metastatic disease underpins the responsiveness shown in the immunological landscape of metastasis. Various hypotheses on the phylogenesis of metastases have been proposed in the past. The primary tumor's secreting factors shape the intratumoral microenvironment and the immune landscape, allowing this progress to be made. Therefore, it is evident that among disseminated tumor cells, there are distinct phenotypes that either carry budding for metastasis or have the ability to obtain this potential or in systemic priming through contact with substantial metastatic niches that have implications for medicinal chemistry. Concurrent immunity signals that the main tumor induces an immune response that may not be strong enough to eradicate the tumor. Immunotherapy's success with some cancer patients shows that it is possible to effectively destroy even advanced-stage tumors by modifying the microenvironment and tumor-immune cell interactions. This review focuses on the metastasome in colorectal carcinoma and the therapeutic implications of site-specific metastasis, systemic priming, tumor spread, and the relationship between the immune system and metastasis.

Quercetin-induced degradation of RhoC suppresses hepatocellular carcinoma invasion and metastasis.

BACKGROUND: Tumor metastasis and recurrence are major causes of mortality in patients with hepatocellular carcinoma (HCC) that is still lack of effective therapeutic targets and drugs. Previous reports implied that ras homolog family member C (RhoC) plays a toxic role on metastasis and proliferation of cancer. METHODS: In this research, the correlation between RhoC and metastasis ability was confirmed by in vitro experiments and TCGA database. We explored whether quercetin could inhibit cell migration or invasion by transwell assay. Real-time PCR, overexpression and ubiquitination assay, etc. were applied in mechanism study. Primary HCC cells and animal models including patient-derived xenografts (PDXs) were employed to evaluate the anti-metastasis effects of quercetin. RESULTS: Clinical relevance and in vitro experiments further confirmed the level of RhoC was positively correlated with invasion and metastasis ability of HCC. Then we uncovered that quercetin could attenuate invasion and metastasis of HCC by downregulating RhoC's level in vitro, in vivo and PDXs. Furthermore, mechanistic investigations displayed quercetin hindered the E3 ligase expression of SMAD specific E3 ubiquitin protein ligase 2 (SMURF2) leading to enhancement of RhoC's ubiquitination and proteasomal degradation. CONCLUSIONS: Our research has revealed the novel mechanisms quercetin regulates degradation of RhoC level by targeting SMURF2 and identified quercetin may be a potential compound for HCC therapy.

Prevention of Metastasis by Suppression of Stemness Genes Using a Combination of microRNAs.

We propose an original strategy for metastasis prevention using a combination of three microRNAs that blocks the dedifferentiation of cancer cells in a metastatic niche owing to the downregulation of stemness genes. Transcriptome microarray analysis was applied to identify the effects of a mixture of microRNAs on the pattern of differentially expressed genes in human breast cancer cell lines. Treatment of differentiated CD44- cancer cells with the microRNA mixture inhibited their ability to form mammospheres in vitro. The combination of these three microRNAs encapsulated into lipid nanoparticles prevented lung metastasis in a mouse model of spontaneous metastasis. The mixture of three microRNAs (miR-195-5p/miR-520a/miR-630) holds promise for the development of an antimetastatic therapeutic that blocks tumor cell dedifferentiation, which occurs at secondary tumor sites and determines the transition of micrometastases to macrometastases.

Recent advances in micro-physiological systems for investigating tumor metastasis and organotropism.

Tumor metastasis involves complex processes that traditional 2D cultures and animal models struggle to fully replicate. Metastatic tumors undergo a multitude of transformations, including genetic diversification, adaptation to diverse microenvironments, and modified drug responses, contributing significantly to cancer-related mortality. Micro-physiological systems (MPS) technology emerges as a promising approach to emulate the metastatic process by integrating critical biochemical, biomechanical, and geometrical cues at a microscale. These systems are particularly advantageous simulating metastasis organotropism, the phenomenon where tumors exhibit a preference for metastasizing to particular organs. Organotropism is influenced by various factors, such as tumor cell characteristics, unique organ microenvironments, and organ-specific vascular conditions, all of which can be effectively examined using MPS. This review surveys the recent developments in MPS research from the past five years, with a specific focus on their applications in replicating tumor metastasis and organotropism. Furthermore, we discuss the current limitations in MPS-based studies of organotropism and propose strategies for more accurately replicating and analyzing the intricate aspects of organ-specific metastasis, which is pivotal in the development of targeted therapeutic approaches against metastatic cancers.

Neural recordings can differentiate between spontaneously metastasizing melanomas and melanomas with low metastatic potential.

Multiple studies report that melanomas are innervated tumors with sensory and sympathetic fibers where these neural fibers play crucial functional roles in tumor growth and metastasis with branch specificity. Yet there is no study which reports the direct neural recording and its pattern during in-vivo progression of the cancer. We performed daily neural recordings from male and female mice bearing orthotopic metastasizing- melanomas and melanomas with low metastatic poential, derived from B16-F10 and B16-F1 cells, respectively. Further, to explore the origins of neural activity, 6-Hydroxidopamine mediated chemical sympathectomy was performed followed by daily microneurographic recordings. We also performed the daily bioluminescent imaging to track in vivo growth of primary tumors and distant metastasis to the cranial area. Our results show that metastasizing tumors display high levels of neural activity while tumors with low metastatic potential lack it indicating that the presence of neural activity is linked to the metastasizing potential of the tumors. Moreover, the neural activity is not continuous over the tumor progression and has a sex-specific temporal patterns where males have two peaks of high neural activity while females show a single peak. The neural peak activity originated in peripheral sympathetic nerves as sympathectomy completely eliminated the peak activity in both sexes. Peak activities were highly correlated with the distant metastasis in both sexes. These results show that sympathetic neural activity is crucially involved in tumor metastasis and has sex-specific role in malignancy initiation.

Decreased Lung Metastasis in Triple Negative Breast Cancer Following Locally Delivered Supratherapeutic Paclitaxel-Loaded Polyglycerol Carbonate Nanoparticle Therapy.

Breast cancer is among the most prevalent malignancies, accounting for 685,000 deaths worldwide in 2020, largely due to its high metastatic potential. Depending on the stage and tumor characteristics, treatment involves surgery, chemotherapy, targeted biologics, and/or radiation therapy. However, current treatments are insufficient for treating or preventing metastatic disease. Herein, we describe supratherapeutic paclitaxel-loaded nanoparticles (81 wt % paclitaxel) to treat the primary tumor and reduce the risk of subsequent metastatic lesions in the lungs. Primary tumor volume and lung metastasis are reduced by day 30, compared to the paclitaxel clinical standard treatment. The ultrahigh levels of paclitaxel afford an immunotherapeutic effect, increasing natural killer cell activation and decreasing NETosis in the lung, which limits the formation of metastatic lesions.

Fibroblasts: invigorated targets in pre-metastatic niche formation.

At present, tumor metastasis still remains the leading contributor to high recurrence and mortality in cancer patients. There have been no clinically effective therapeutic strategies for treating patients with metastatic cancer. In recent years, a growing body of evidence has shown that the pre-metastatic niche (PMN) plays a crucial role in driving tumor metastasis. Nevertheless, a clear and detailed understanding of the formation of PMN is still lacking given the fact that PMN formation involves in a wealth of complicated communications and underlying mechanisms between primary tumors and metastatic target organs. Despite that the roles of numerous components including tumor exosomes and extracellular vesicles in influencing the evolution of PMN have been well documented, the involvement of cancer-associated fibroblasts (CAFs) in the tumor microenvironment for controlling PMN formation is frequently overlooked. It has been increasingly recognized that fibroblasts trigger the formation of PMN by virtue of modulating exosomes, metabolism and so on. In this review, we mainly summarize the underlying mechanisms of fibroblasts from diverse origins in exerting impacts on PMN evolution, and further highlight the prospective strategies for targeting fibroblasts to prevent PMN formation.

How important is EMT for cancer metastasis?

Epithelial-to-mesenchymal transition (EMT), a biological phenomenon of cellular plasticity initially reported in embryonic development, has been increasingly recognized for its importance in cancer progression and metastasis. Despite tremendous progress being made in the past 2 decades in our understanding of the molecular mechanism and functional importance of EMT in cancer, there are several mysteries around EMT that remain unresolved. In this Unsolved Mystery, we focus on the variety of EMT types in metastasis, cooperative and collective EMT behaviors, spatiotemporal characterization of EMT, and strategies of therapeutically targeting EMT. We also highlight new technical advances that will facilitate the efforts to elucidate the unsolved mysteries of EMT in metastasis.

C9orf10/Ossa regulates the bone metastasis of established lung adenocarcinoma cell subline H322L-BO4 in a mouse model.

Lung cancer frequently metastasizes to the bones. An in vivo model is urgently required to identify potential therapeutic targets for the prevention and treatment of lung cancer with bone metastasis. We established a lung adenocarcinoma cell subline (H322L-BO4) that specifically showed metastasis to the leg bones and adrenal glands. This was achieved by repeated isolation of metastatic cells from the leg bones of mice. The cells were intracardially injected into nude mice. Survival was prolonged for mice that received H322L-BO4 cells versus original cells (H322L). H322L-BO4 cells did not exhibit obvious changes in general in vitro properties associated with the metastatic potential (e.g., cell growth, migration, and invasion) compared with H322L cells. However, the phosphorylation of chromosome 9 open reading frame 10/oxidative stress-associated Src activator (C9orf10/Ossa) was increased in H322L-BO4 cells. This result confirmed the increased anchorage independence through C9orf10/Ossa-mediated activation of Src family tyrosine kinase. Reduction of C9orf10/Ossa by shRNA reduced cells' metastasis to the leg bone and prolonged survival in mice. These findings indicate that H322L-BO4 cells can be used to evaluate the effect of candidate therapeutic targets against bone metastatic lung cancer cells. Moreover, C9orf10/Ossa may be a useful target for treatment of lung cancer with bone metastasis.

Deep whole-genome analysis of 494 hepatocellular carcinomas.

Over half of hepatocellular carcinoma (HCC) cases diagnosed worldwide are in China1-3. However, whole-genome analysis of hepatitis B virus (HBV)-associated HCC in Chinese individuals is limited4-8, with current analyses of HCC mainly from non-HBV-enriched populations9,10. Here we initiated the Chinese Liver Cancer Atlas (CLCA) project and performed deep whole-genome sequencing (average depth, 120×) of 494 HCC tumours. We identified 6 coding and 28 non-coding previously undescribed driver candidates. Five previously undescribed mutational signatures were found, including aristolochic-acid-associated indel and doublet base signatures, and a single-base-substitution signature that we termed SBS_H8. Pentanucleotide context analysis and experimental validation confirmed that SBS_H8 was distinct to the aristolochic-acid-associated SBS22. Notably, HBV integrations could take the form of extrachromosomal circular DNA, resulting in elevated copy numbers and gene expression. Our high-depth data also enabled us to characterize subclonal clustered alterations, including chromothripsis, chromoplexy and kataegis, suggesting that these catastrophic events could also occur in late stages of hepatocarcinogenesis. Pathway analysis of all classes of alterations further linked non-coding mutations to dysregulation of liver metabolism. Finally, we performed in vitro and in vivo assays to show that fibrinogen alpha chain (FGA), determined as both a candidate coding and non-coding driver, regulates HCC progression and metastasis. Our CLCA study depicts a detailed genomic landscape and evolutionary history of HCC in Chinese individuals, providing important clinical implications.

Recently reported cell migration inhibitors: Opportunities and challenges for antimetastatic agents.

Antimetastatic agents are highly desirable for cancer treatment because of the severe medical challenges and high mortality resulting from tumor metastasis. Having demonstrated antimetastatic effects in numerous in vitro and in vivo studies, migration inhibitors present significant opportunities for developing a new class of anticancer drugs. To provide a useful overview on the latest research in migration inhibitors, this article first discusses their therapeutic significance, targetable proteins, and developmental avenues. Subsequently it reviews over 20 representative migration inhibitors reported in recent journals in terms of their inhibitory mechanism, potency, and potential clinical utility. The relevance of the target proteins to cellular migratory function is focused on as it is crucial for assessing the overall efficacy of the inhibitors.

Glycan-Lectin interactions between platelets and tumor cells drive hematogenous metastasis.

Glycosylation is a ubiquitous cellular or microenvironment-specific post-translational modification that occurs on the surface of normal cells and tumor cells. Tumor cell-associated glycosylation is involved in hematogenous metastasis. A wide variety of tumors undergo aberrant glycosylation to interact with platelets. As platelets have many opportunities to engage circulating tumor cells, they represent an important avenue into understanding the role glycosylation plays in tumor metastasis. Platelet involvement in tumor metastasis is evidenced by observations that platelets protect tumor cells from damaging shear forces and immune system attack, aid metastasis through the endothelium at specific sites, and facilitate tumor survival and colonization. During platelet-tumor-cell interactions, many opportunities for glycan-ligand binding emerge. This review integrates the latest information about glycans, their ligands, and how they mediate platelet-tumor interactions. We also discuss adaptive changes that tumors undergo upon glycan-lectin binding and the impact glycans have on targeted therapeutic strategies for treating tumors in clinical settings.

Tumor hematogenous metastasis is a serious threat to the survival and prognosis of patients, and a variety of factors help this process to occur, and platelets are also involved. During tumor cell metastasis, platelets can adhere to each other and tumor cells, a phenomenon that leads to the immunity of tumor cells from various threats in metastasis, including immune attacks, shearing forces, etc. Scientists have shown that the adhesion effect between platelets and tumor cells is often dependent on various types of sugars, which are not the sugars we ingest. These sugars often appear as glycosylation modifications on the proteins of the cells, including normal glycosylation modifications and some abnormal structures that only appear on tumor cells, and their ligands, lectins, are also present on the surface of the tumor cells or platelets. Their combination results in the better adaptation of tumor cells to the metastatic process, where proteins such as P-selectin, CLEC-2, and Galectins have been more studied. Focusing on Glycan-Lectin interactions between platelets and tumor cells, related studies help us to further understand tumor metastasis, and intervene in this binding and develop related drugs with great potential.

Oncoprotein SET-associated transcription factor ZBTB11 triggers lung cancer metastasis.

Metastasis is the major cause of lung cancer-related death, but the mechanisms governing lung tumor metastasis remain incompletely elucidated. SE translocation (SET) is overexpressed in lung tumors and correlates with unfavorable prognosis. Here we uncover SET-associated transcription factor, zinc finger and BTB domain-containing protein 11 (ZBTB11), as a prometastatic regulator in lung tumors. SET interacts and collaborates with ZBTB11 to promote lung cancer cell migration and invasion, primarily through SET-ZBTB11 complex-mediated transcriptional activation of matrix metalloproteinase-9 (MMP9). Additionally, by transcriptional repression of proline-rich Gla protein 2 (PRRG2), ZBTB11 links Yes-associated protein 1 (YAP1) activation to drive lung tumor metastasis independently of SET-ZBTB11 complex. Loss of ZBTB11 suppresses distal metastasis in a lung tumor mouse model. Overexpression of ZBTB11 is recapitulated in human metastatic lung tumors and correlates with diminished survival. Our study demonstrates ZBTB11 as a key metastatic regulator and reveals diverse mechanisms by which ZBTB11 modulates lung tumor metastasis.