MRPL13 is a metastatic and prognostic marker of breast cancer: A silico analysis accompanied with experimental validation.

BACKGROUND: Although progress has been made in accurate diagnosis and targeted treatments, breast cancer (BC) patients with metastasis still present a grim prognosis. With the continuous emergence and development of new personalized and precision medicine targeting specific tumor biomarkers, there is an urgent need to find new metastatic and prognostic biomarkers for BC patients. METHODS: We were dedicated to identifying genes linked to metastasis and prognosis in breast cancer through a combination of in silico analysis and experimental validation. RESULTS: A total of 25 overlap differentially expressed genes were identified. Ten hub genes (namely MRPL13, CTR9, TCEB1, RPLP0, TIMM8B, METTL1, GOLT1B, PLK2, PARL and MANBA) were identified and confirmed. MRPL13, TCEB1 and GOLT1B were shown to be associated with the worse overall survival (OS) and were optionally chosen for further verification by western blot. Only MRPL13 was found associated with cell invasion, and the expression of MRPL13 in metastatic BC was significantly higher than in primary BC. CONCLUSION: We proposed MRPL13 could be a potential novel biomarker for the metastasis and prognosis of breast cancer.

An ultra-long-acting L-asparaginase synergizes with an immune checkpoint inhibitor in starvation-immunotherapy of metastatic solid tumors.

Metastasis stands as the primary contributor to mortality associated with tumors. Chemotherapy and immunotherapy are frequently utilized in the management of metastatic solid tumors. Nevertheless, these therapeutic modalities are linked to serious adverse effects and limited effectiveness in preventing metastasis. Here, we report a novel therapeutic strategy named starvation-immunotherapy, wherein an immune checkpoint inhibitor is combined with an ultra-long-acting L-asparaginase that is a fusion protein comprising L-asparaginase (ASNase) and an elastin-like polypeptide (ELP), termed ASNase-ELP. ASNase-ELP's thermosensitivity enables it to generate an in-situ depot following an intratumoral injection, yielding increased dose tolerance, improved pharmacokinetics, sustained release, optimized biodistribution, and augmented tumor retention compared to free ASNase. As a result, in murine models of oral cancer, melanoma, and cervical cancer, the antitumor efficacy of ASNase-ELP by selectively and sustainably depleting L-asparagine essential for tumor cell survival was substantially superior to that of ASNase or Cisplatin, a first-line anti-solid tumor medicine, without any observable adverse effects. Furthermore, the combination of ASNase-ELP and an immune checkpoint inhibitor was more effective than either therapy alone in impeding melanoma metastasis. Overall, the synergistic strategy of starvation-immunotherapy holds excellent promise in reshaping the therapeutic landscape of refractory metastatic tumors and offering a new alternative for next-generation oncology treatments.

The Role of Surgery in "Oligometastatic" Pancreas Cancer.

The majority of patients diagnosed with pancreatic cancer already have metastatic disease at the time of presentation, which results in a 5-year survival rate of only 13%. However, multiagent chemotherapy regimens can stabilize the disease in select patients with limited metastatic disease. For such patients, a combination of curative-intent therapy and systemic therapy may potentially enhance outcomes compared to using systemic therapy alone. Of note, the evidence supporting this approach is primarily derived from retrospective studies and may carry a significant selection bias. Looking ahead, ongoing prospective trials are exploring the efficacy of curative-intent therapy in managing oligometastatic pancreatic cancer and the implementation of treatment strategies based on specific biomarkers. The emergence of these trials, coupled with the development of less invasive therapeutic modalities, provides hope for patients with oligometastatic pancreatic cancer.

Identification of Wandering Masses and Tumor Heterogeneity on 68Ga-DOTATATE and 18F-FDG PET/CT in Metastatic Grade II Neuroendocrine Tumor with Increased Somatostatin Receptor Expression After Combined Chemotherapy and PRRT.

Neuroendocrine tumors (NETs) may manifest as large masses in the abdominopelvic region that exhibit mobility and shifting, potentially leading to diagnostic uncertainty both before and after treatment. A meticulous analysis of PET/CT scans is advantageous in accurately identifying the precise location of large abdominopelvic masses. Tumor heterogeneity may be present in NETs with large abdominopelvic masses and may be easily identified on dual-tracer (68Ga-DOTATATE and 18F-FDG) PET/CT scans. In this scenario, the combined use of chemotherapy and peptide receptor radionuclide therapy is a more effective treatment option than monotherapy. Here, we present a case of a NET with wandering, large, heterogeneous masses in the abdominopelvic regions that were identified using dual-tracer PET/CT. After the administration of temozolomide chemotherapy in a combined chemotherapy-peptide receptor radionuclide therapy approach, we observed an upregulation in the expression of somatostatin receptor in the abdominopelvic masses.

Impact of different visceral metastatic sites on survival in metastatic prostate cancer patients.

INTRODUCTION: Visceral metastasis is an important predictor for poor outcomes in prostate cancer, however, the prognostic significance surrounding the specific sites of visceral metastasis remains unclear. The aim of this study was to evaluate the impact of different visceral metastatic sites on survival in patients with prostate cancer. METHODS: We identified patients with metastatic prostate cancer between January 1, 2010 and December 31, 2023 using the TriNetX database. Patients were divided into 4 cohorts according to their specific metastatic sites: lung metastases, brain metastases, liver metastases, and bone metastases. Survival analysis was calculated using the Kaplan-Meier method and Cox regression models. RESULTS: In total, 59,875 patients diagnosed with metastatic prostate cancer were identified, with 39,495 (65.2%) having bone metastases, 7,573 (12.5%) lung metastases, 5,240 (8.7%) brain metastases, and 7,567 (12.5%) liver metastases. The median overall survival was 44.4 months for patients with bone metastases, 31.9 months for lung metastases, 9.6 months for brain metastases, and 10 months for liver metastases. Lung metastases were associated with an improved survival when compared with liver and brain metastases. For patients with two visceral metastatic sites or concomitant bone metastases, liver metastases were related to worse outcomes. Asian patients experienced better OS than Caucasian and African American patients in visceral metastatic prostate cancer. CONCLUSION: Patients with lung metastases experienced better survival outcomes in prostate cancer with only one visceral metastatic site. Liver metastases were associated with worse outcomes when there were two visceral metastatic sites combined or concomitant bone metastases. Asian patients displayed improved survival rates when compared with both Caucasian and African American patients in visceral metastatic prostate cancer.

A randomized phase III trial of stereotactic ablative radiotherapy for patients with up to 10 oligometastases and a synchronous primary tumor (SABR-SYNC): study protocol.

BACKGROUND: Emerging randomized data, mostly from phase II trials, have suggested that patients with oligometastatic cancers may benefit from ablative treatments such as stereotactic ablative radiotherapy (SABR). However, phase III data testing this paradigm are lacking, and many studies have examined SABR in the setting of metachronous oligometastatic disease. The goal of the SABR-SYNC trial is to assess the effect of SABR in patients with oligometastatic cancers and a synchronous primary tumor. METHODS: One hundred and eighty patients will be randomized in a 1:2 ratio between standard of care (SOC) palliative-intent treatments vs. SOC + ablative therapy (SABR preferred) to all sites of known disease. Randomization will be stratified based on histology and number of metastases at enrollment. SABR may be delivered in 1-, 3- and 5-fraction regimens, with recommended doses of 20 Gy, 30 Gy, and 35 Gy, respectively. Non-SABR local modalities (e.g. surgery, thermal ablation, conventional radiation) may be used for treatment of the primary or metastases at the discretion of the treating physicians, if those modalities are clinically preferred. The primary endpoint is overall survival, and secondary endpoints include progression-free survival, time to development of new metastatic lesions, time to initiation of next systemic therapy, quality of life, and toxicity. Translational endpoints include assessment of circulating tumor DNA and immunological predictors of outcomes. DISCUSSION: SABR-SYNC will provide phase III data to assess the impact of SABR on overall survival in a population of patients with synchronous oligometastases. The translational component will attempt to identify novel prognostic and predictive biomarkers to aid in clinical decision making. TRIAL REGISTRATION: Clinicaltrials.gov NCT05717166 (registration date: Feb. 8, 2023).

Clinico-biological factors predicting the benefit of the LV5FU2 maintenance strategy as a first-line therapy in patients with metastatic pancreatic cancer.

INTRODUCTION: Predictive markers of LV5FU2 maintenance benefit after first-line induction with FOLFIRINOX in patients with metastatic pancreatic cancer are necessary to select patients who will not be harmed by this strategy. PATIENTS AND METHODS: We focused on patients who received 12 cycles of FOLFIRINOX (arm A, N = 88) or 8 cycles of FOLFIRINOX followed by LV5FU2 maintenance in controlled patients (arm B, N = 91) from the PRODIGE-35 trial. Prognostic factors and predictors of efficiency were identified by using Cox regression. Median progression-free survival (PFS), overall survival (OS), and time to deterioration of quality of life (TTD-QoL) were evaluated. RESULTS: Poor independent prognostic factors were primary tumor in place, age <65 years and the presence of liver metastases for PFS, a baseline neutrophil/lymphocyte ratio (NLR) ≥5 and CA19.9 ≥500 UI/L for OS, independent of the treatment arm. Patients with one metastatic site had a longer PFS in arm A, whereas patients with ≥2 metastatic sites had a longer PFS in arm B. We also identified predictors of OS and TTD-QoL in arm B but these differences were not statistically significant. CONCLUSION: Except for patients with one metastatic site who benefited more from 12 cycles of FOLFIRINOX, a maintenance strategy with LV5FU2 should be widely offered to mPC patients whose survival and QoL are preserved after 4 months of FOLFIRINOX. (ClinicalTrials.gov: NCT02352337).

Increasing monocytes after lung cancer surgery triggers the outgrowth of distant metastases, causing recurrence.

Patients with lung cancer have a high incidence of tumor recurrence even after curative surgical resection. Some reports indicated that immunosuppressive cells induced by surgical stress could contribute to tumor recurrence after surgery; however, the underlying mechanisms are not fully understood. In this study, we found that increased postoperative blood monocytes served as a risk factor for tumor recurrence in 192 patients with non-small cell lung cancer (NSCLC). We established the lung cancer recurrent mouse model after tumor resection and showed that the surgical stress immediately increased the level of serum monocyte chemoattractant protein-1 (MCP-1), which subsequently increased blood monocytes. These blood monocytes were rapidly recruited into distant micrometastases and became tumor growth-promoting tumor associated macrophages (TAMs). Furthermore, even after the blood MCP-1 and monocytes decreased enough 72 h after tumor resection, TAMs in micrometastases remained rich because the MCP-1 secreted by micrometastases themselves continued to recruit monocytes around the tumor. Consequently, tumor resection triggered the outgrowth of distant metastases via the MCP-1-Monocyte-TAM axis. When we administered the MCP-1 inhibitor to the lung cancer recurrent model mice, blood monocytes decreased after tumor resection, and TAMs in micrometastases also dramatically decreased. Finally, peri- and postoperative treatment with the MCP-1 inhibitor suppressed distant metastases after surgery. Targeting the MCP-1-Monocyte-TAM axis may inhibit surgical stress-induced NSCLC recurrence by attenuating postoperative immunosuppressive monocytes in micrometastases.

Circulating Tumor DNA and Survival in Metastatic Breast Cancer: A Systematic Review and Meta-Analysis.

Importance: Metastatic breast cancer (MBC) poses a substantial clinical challenge despite advancements in diagnosis and treatment. While tissue biopsies offer a static snapshot of disease, liquid biopsy-through detection of circulating tumor DNA (ctDNA)-provides minimally invasive, real-time insight into tumor biology. Objective: To determine the association between ctDNA and survival outcomes in patients with MBC. Data Sources: An electronic search was performed in 5 databases (CINAHL, Cochrane Library, Embase, Medline, and Web of Science) and included all articles published from inception until October 23, 2023. Study Selection: To be included in the meta-analysis, studies had to (1) include women diagnosed with MBC; (2) report baseline plasma ctDNA data; and (3) report overall survival, progression-free survival, or disease-free survival with associated hazards ratios. Data Extraction and Synthesis: Titles and abstracts were screened independently by 2 authors. Data were pooled using a random-effects model. This study adhered to the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) reporting guideline, and quality was assessed using the Newcastle-Ottawa Scale. Main Outcomes and Measures: The primary study outcome was the association between detection of specific genomic alterations in ctDNA with survival outcomes. Secondary objectives were associations of study methodology with survival. Results: Of 3162 articles reviewed, 37 met the inclusion criteria and reported data from 4264 female patients aged 20 to 94 years. Aggregated analysis revealed a significant association between ctDNA detection and worse survival (hazard ratio, 1.40; 95% CI, 1.22-1.58). Subgroup analysis identified significant associations of TP53 and ESR1 alterations with worse survival (hazard ratios, 1.58 [95% CI, 1.34-1.81] and 1.28 [95% CI, 0.96-1.60], respectively), while PIK3CA alterations were not associated with survival outcomes. Stratifying by detection method, ctDNA detection through next-generation sequencing and digital polymerase chain reaction was associated with worse survival (hazard ratios, 1.48 [95% CI, 1.22-1.74] and 1.28 [95% CI, 1.05-1.50], respectively). Conclusions and Relevance: In this systematic review and meta-analysis, detection of specific genomic alterations in ctDNA was associated with worse overall, progression-free, and disease-free survival, suggesting its potential as a prognostic biomarker in MBC. These results may help guide the design of future studies to determine the actionability of ctDNA findings.

Hsa_circ_0000520 suppresses vasculogenic mimicry formation and metastasis in bladder cancer through Lin28a/PTEN/PI3K signaling.

BACKGROUND: Vasculogenic mimicry (VM) is a potential cause of resistance to antiangiogenic therapy and is closely related to the malignant progression of tumors. It has been shown that noncoding RNAs play an important role in the formation of VM in malignant tumors. However, the role of circRNAs in VM of bladder cancer and the regulatory mechanisms are unclear. METHODS: Firstly, hsa_circ_0000520 was identified to have circular character by Sanger sequencing and Rnase R assays. Secondly, the potential clinical value of hsa_circ_0000520 was explored by quantitative real-time polymerase chain reaction (qRT-PCR) and fluorescence in situ hybridization (FISH) of clinical specimens. Thirdly, the role of hsa_circ_0000520 in bladder cancer invasion, migration, and VM formation was examined by in vivo and in vitro experiments. Finally, the regulatory mechanisms of hsa_circ_0000520 in the malignant progression of bladder cancer were elucidated by RNA binding protein immunoprecipitation (RIP), RNA pulldown, co-immunoprecipitation (co-IP), qRT-PCR, Western blot (WB), and fluorescence co-localization. RESULTS: Hsa_circ_0000520 was characterized as a circular RNA and was lowly expressed in bladder cancer compared with the paracancer. Bladder cancer patients with high expression of hsa_circ_0000520 had better survival prognosis. Functionally, hsa_circ_0000520 inhibited bladder cancer invasion, migration, and VM formation. Mechanistically, hsa_circ_0000520 acted as a scaffold to promote binding of UBE2V1/UBC13 to Lin28a, further promoting the ubiquitous degradation of Lin28a, improving PTEN mRNA stability, and inhibiting the phosphorylation of the PI3K/AKT pathway. The formation of hsa_circ_0000520 in bladder cancer was regulated by RNA binding protein QKI. CONCLUSIONS: Hsa_circ_0000520 inhibits metastasis and VM formation in bladder cancer and is a potential target for bladder cancer diagnosis and treatment.

Circulating tumor cells: from new biological insights to clinical practice.

The primary reason for high mortality rates among cancer patients is metastasis, where tumor cells migrate through the bloodstream from the original site to other parts of the body. Recent advancements in technology have significantly enhanced our comprehension of the mechanisms behind the bloodborne spread of circulating tumor cells (CTCs). One critical process, DNA methylation, regulates gene expression and chromosome stability, thus maintaining dynamic equilibrium in the body. Global hypomethylation and locus-specific hypermethylation are examples of changes in DNA methylation patterns that are pivotal to carcinogenesis. This comprehensive review first provides an overview of the various processes that contribute to the formation of CTCs, including epithelial-mesenchymal transition (EMT), immune surveillance, and colonization. We then conduct an in-depth analysis of how modifications in DNA methylation within CTCs impact each of these critical stages during CTC dissemination. Furthermore, we explored potential clinical implications of changes in DNA methylation in CTCs for patients with cancer. By understanding these epigenetic modifications, we can gain insights into the metastatic process and identify new biomarkers for early detection, prognosis, and targeted therapies. This review aims to bridge the gap between basic research and clinical application, highlighting the significance of DNA methylation in the context of cancer metastasis and offering new avenues for improving patient outcomes.

miR-7160 inhibits gastric cancer cell proliferation and metastasis by silencing SIX1.

Upregulation of homeoprotein SIX1 in gastric cancer (GC) is related to tumour proliferation and invasion. MicroRNA-7160 (miR-7160) is a homeoprotein SIX1-targeting miRNA that downregulates miR-7160, leading to cancer development. Total gastric cancer samples were collected from six patients, and relative expression levels of SIX1 mRNA and miRNAs were analysed by qRT-PCR. To evaluate the regulation of SIX1 by miR-7160, pGL3-SIX1-mut, pGL3-SIX1, and miR-7160 mimics transfected into cells using lipofectamine 2000. After transfection, proliferation and apoptosis in cultured cells were assessed using the nuclear TUNEL staining and CCK8 reagent, respectively. We demonstrated that the downregulation of miR-7160 in human gastric cancer cells is related to the upregulation of SIX1 mRNA. In gastric cancer cell lines, miR-7160 overexpression could downregulate the expression and inhibit cancer cell proliferation and growth in vitro. However, overexpression of miR-7160 did not increase gastric cancer cell apoptosis. In vitro downregulation of SIX1 decreased vimentin, N-cadherin, and other EMT-related gene expression and increased E-cadherin expression. In brief, miR-7160, by targeting SIX1, inhibits gastric cancer proliferation and cell growth in vitro, which provides an idea for introducing a new treatment option for gastric cancer.

Oxaliplatin-induced peripheral neuropathy with hepatic arterial versus intravenous infusion in metastatic colorectal cancer.

BACKGROUND: Oxaliplatin, a major drug in metastatic colorectal cancer (mCRC), is responsible for cumulative, dose-limiting peripheral neuropathy (PN). Whether the hepatic arterial infusion (HAI) route can limit oxaliplatin-induced PN in comparison with the intravenous (IV) route has not been specifically explored so far. METHODS: We compared the frequency and severity of PN in oxaliplatin-naive patients with mCRC included in trials that evaluated treatment with oxaliplatin administered either by HAI (ACCORD 04, CHOICE, OSCAR, and PACHA-01 trials) or by IV route (FFCD 2000-05 trial). We retrieved anonymized, prospectively collected data from trial databases for the ACCORD 04, CHOICE, and FFCD 2000-05 trials and through a review of Gustave Roussy patients' electronic medical records for PACHA-01 and OSCAR trials. The primary endpoint was the incidence of clinically significant PN (grades 2 to 4) according to the cumulative dose of oxaliplatin received. Secondary endpoints were time to onset of neuropathy as a function of the cumulative dose of oxaliplatin, discontinuation of oxaliplatin for neurotoxicity, and safety. RESULTS: A total of 363 patients were included (IV, 300; HAI, 63). In total, 180 patients in the IV group (60%) and 30 patients in the HAI group (48%) developed clinically significant PN, with no significant difference between the two groups (p = 0.23). No difference was shown in the time to onset of PN either (p = 0.23). CONCLUSION: The administration of oxaliplatin HAI rather than IV in the treatment of mCRC does not reduce the incidence, precocity, and severity of PN.

SPHK1 promotes bladder cancer metastasis via PD-L2/c-Src/FAK signaling cascade.

SPHK1 (sphingosine kinase type 1) is characterized as a rate-limiting enzyme in sphingolipid metabolism to phosphorylate sphingosine into sphingosine-1-phosphate (S1P) that can bind to S1P receptors (S1PRs) to initiate several signal transductions leading to cell proliferation and survival of normal cell. Many studies have indicated that SPHK1 is involved in several types of cancer development, however, a little is known in bladder cancer. The TCGA database analysis was utilized for analyzing the clinical relevance of SPHK1 in bladder cancer. Through CRISPR/Cas9 knockout (KO) and constitutive activation (CA) strategies on SPHK1 in the bladder cancer cells, we demonstrated the potential downstream target could be programmed cell death 1 ligand 2 (PD-L2). On the other hand, we demonstrated that FDA-approved SPHK1 inhibitor Gilenya® (FTY720) can successfully suppress bladder cancer metastasis by in vitro and in vivo approaches. This finding indicated that SPHK1 as a potent therapeutic target for metastatic bladder cancer by dissecting the mechanism of action, SPHK1/S1P-elicited Akt/ß-catenin activation promoted the induction of PD-L2 that is a downstream effector in facilitating bladder cancer invasion and migration. Notably, PD-L2 interacted with c-Src that further activates FAK. Here, we unveil the clinical relevance of SPHK1 in bladder cancer progression and the driver role in bladder cancer metastasis. Moreover, we demonstrated the inhibitory effect of FDA-approved SPHK1 inhibitor FTY720 on bladder cancer metastasis from both in vitro and in vivo models.

CCDC113 promotes colorectal cancer tumorigenesis and metastasis via TGF-ß signaling pathway.

Colorectal cancer (CRC) is the second leading cause of cancer-related mortality worldwide. Although CRC patients' survival is improved with surgical resection and immunotherapy, metastasis and recurrence remain major problems leading to poor prognosis. Therefore, exploring pathogenesis and identifying specific biomarkers are crucial for CRC early diagnosis and targeted therapy. CCDC113, a member of CCDC families, has been reported to play roles in ciliary assembly, ciliary activity, PSCI, asthma and early lung cancer diagnosis. However, the functions of CCDC113 in CRC still remain unclear. In this study, we find that CCDC113 is significantly highly expressed in CRC. High expression of CCDC113 is significantly correlated with CRC patients' poor prognosis. CCDC113 is required for CRC tumorigenesis and metastasis. RNA-seq and TCGA database analysis indicate that CCDC113 is positively correlated with TGF-ß signaling pathway. TGF-ß signaling pathway inhibitor galunisertib could reverse the increased proliferation and migration ability of CRC cells caused by CCDC113 overexpression in vitro and in vivo. These results indicate that CCDC113 promotes CRC tumorigenesis and metastasis via TGF-ß signaling pathway. In conclusion, it is the first time to explore the functions and mechanisms of CCDC113 in CRC tumorigenesis and metastasis. And CCDC113 may be a potential biomarker and therapeutic target for CRC intervention.

The Antimicrobial Peptide Merecidin Inhibit the Metastasis of Triple-Negative Breast Cancer by Obstructing EMT via miR-30d-5p/Vimentin.

Purpose: To investigate the inhibitory effect of antimicrobial peptide merecidin on triple-negative breast cancer (TNBC) and the mechanism of inhibiting epithelial-mesenchymal transformation (EMT) by regulating miR-30d-5p/vimentin. Methods: TNBC cell lines (MDA-MB-231, MDA-MB-468) were treated with merecidin to assess proliferation, migration, invasion ability, and EMT. Confocal laser localization was used to examine the role of merecidin and TNBC cells. The relationship between merecidin and miR-30d-5p was determined through RT-qPCR and dual-luciferase reporter gene, and the relationship between merecidin and vimentin was verified through pulling down the experiment. The effects of miR-30d-5p on the migration and invasion ability of TNBC cells were confirmed through scratch and transwell experiments. Vimentin levels, tumor volume, shape, size, and weight were observed in the MDA-MB-231 subcutaneous tumor model in nude mice. Results: merecidin inhibited the proliferation, migration, invasion, and EMT of TNBC cells. merecidin was primarily located in the cytoplasm of TNBC cells, and the expression of miR-30d-5p was low in TNBC cells. merecidin significantly up-regulated the expression of miR-30d-5p. miR-30d-5p negatively regulated vimentin. merecidin could bind to vimentin in vitro. miR-30d-5p inhibited the migration and invasion ability of TNBC cells, while vimentin promoted their migration and invasion ability. Down-regulation of miR-30d-5p or overexpression of vimentin partially counteracted the inhibitory effects of merecidin on TNBC cell migration, invasion ability, and EMT. In nude mouse tumor models, merecidin significantly suppressed tumor growth. Conclusion: Merecidin effectively blocks the EMT process and inhibits the migration and invasion of TNBC cells by regulating miR-30d-5p/vimentin.

FOXF1 inhibits invasion and metastasis of lung adenocarcinoma cells and enhances anti-tumor immunity via MFAP4/FAK signal axis.

Based on the joint analysis of multi-omic data and the biological experiments, we demonstrate that FOXF1 inhibits invasion and metastasis of lung adenocarcinoma cells and enhances anti-tumor immunity via regulating MFAP4/FAK signal axis in this study. The levels of FOXF1 and MFAP4 are significantly down-regulated in LUAD, and the increased levels of two genes can improve the clinical prognosis of LUAD patients. Fluorescein reporter gene determination, chromatin immunoprecipitation and gene co-expression analysis indicate that MFAP4 level is positively regulated by transcription factor FOXF1. The function enrichment analysis shows that the levels of FOXF1 and MFAP4 are closely associated with an enrichment of tumor metastasis signatures. FOXF1 can inhibit the migration and invasion of LAUD cells by transcriptionally activating MFAP4 expression. And the overexpression of FOXF1/MFAP4 can reduce focal adhesion kinase (FAK) phosphorylation, while their knockdown result in the opposite effects. The increased levels of FOXF1/MFAP4 enhance the antitumor immunity by increasing the infiltration of dendritic cells and CD4+ T cells, and the interactions between LUAD cells and immune cells, and activating multiple anti-tumor immunity-related pathways. In conclusion, our study reveals the potential function of FOXF1/MFAP4/FAK signal axis in inhibiting metastasis of LUAD cells and modulating anti-tumor immunity of LUAD patients.

Exosomal miR-4745-5p/3911 from N2-polarized tumor-associated neutrophils promotes gastric cancer metastasis by regulating SLIT2.

Tumor cells remodel the phenotype and function of tumor microenvironment (TME) cells to favor tumor progression. Previous studies have shown that neutrophils in TME are polarized to N2 tumor-associated neutrophils (TANs) by tumor derived factors, thus promoting tumor growth and metastasis, angiogenesis, therapy resistance, and immunosuppression. Exosomes act as critical intercellular messengers in human health and diseases including cancer. So far, the biological roles of exosomes from N2 TANs in gastric cancer have not been well characterized. Herein, we represented the first report that exosomes from N2 TANs promoted gastric cancer metastasis in vitro and in vivo. We found that exosomes from N2 TANs transferred miR-4745-5p/3911 to gastric cancer cells to downregulate SLIT2 (slit guidance ligand 2) gene expression. Adenovirus-mediated overexpression of SLIT2 reversed the promotion of gastric cancer metastasis by N2 TANs derived exosomes. We further revealed that gastric cancer cells induced glucose metabolic reprogramming in neutrophils through exosomal HMGB1 (high mobility group protein B1)/NF-κB pathway, which mediated neutrophil N2 polarization and miR-4745-5p/3911 upregulation. We further employed ddPCR (droplet digital PCR) to detect the expression of miR-4745-5p/3911 in N2 TANs exosomes from human serum samples and found their increased levels in gastric cancer patients compared to healthy controls and benign gastric disease patients. Conclusively, our results indicate that N2 TANs facilitate cancer metastasis via regulation of SLIT2 in gastric cancer cells by exosomal miR-4745-5p/3911, which provides a new insight into the roles of TME cells derived exosomes in gastric cancer metastasis and offers a potential biomarker for gastric cancer diagnosis.