Albumin-based nanosystem for dual-modality imaging-guided chem-phototherapy against immune-cold triple-negative breast cancer.

Triple-negative breast cancer is a highly aggressive and metastatic tumor; diagnosing it in the early stages is still difficult, and the prognosis for conventional radio-chemotherapy and immunotreatment is not promising due to cancer's immunosuppressive microenvironment. The utilization of protein-based nanosystem has proven to be effective in delivering agents with limited adverse effects, yet the combination of diagnosis and treatment remains a difficult challenge. This research took advantage of natural albumin and organic molecules to construct a self-assemble core-shell nanostructure combining with superparamagnetic iron oxide nanocrystals and heptamethine cyanine dye IR780 through non-covalent interactions. This nanocomposite successfully decreased the transverse relaxation time of the magnetic resonance hydrogen nucleus, resulting in outstanding T2 imaging, as well as emitting near-infrared II fluorescence, thereby the resulting dual-modality imaging tool was applied to improve diagnostic competency. It is noteworthy that the nanocomposites exhibited impressive enzyme-like catalytic and photothermal capabilities, resulting in a successful activation of the immune system to efficiently suppress distant metastatic lesions in vivo. Consequently, this nano-drug-based therapy could be an advantageous asset in reinforcing the immune system and hindering the growth and reappearance of the immune-cold breast cancer.

Circular RNA circHERC4 as a novel oncogenic driver to promote tumor metastasis via the miR-556-5p/CTBP2/E-cadherin axis in colorectal cancer.

BACKGROUND: The main cause of death in colorectal cancer patients is metastasis. Accumulating evidences suggest that circRNA plays pivotal roles in cancer initiation and development. However, the underlying molecular mechanisms of circRNAs that orchestrate cancer metastasis remain vague and need further clarification. METHODS: Two paired CRC and adjacent normal tissues were used to screen the upregulated circRNAs by circRNA-seq; then, cell invasion assay was applied to confirm the functional invasion-related circRNAs. According to the above methods, circHERC4 (hsa_circ_0007113) was selected for further research. Next, we investigated the clinical significance of circHERC4 in a large cohort of patients with CRC. The oncogenic activity of circHERC4 was investigated in both CRC cell lines and animal xenograft studies. Finally, we explored the molecular mechanisms underlying circHERC4 as a malignant driver. RESULTS: We demonstrated that circHERC4 was aberrantly elevated in CRC tissues (P < 0.001), and was positively associated with lymph node metastasis and advanced tumor grade (P < 0.01). Notably, the expression of circHERC4 was associated with worse survival in patients with CRC. Silencing of circHERC4 significantly inhibited the proliferation and migration of two highly aggressive CRC cell lines and reduced liver and lung metastasis in vivo. Mechanistically, we revealed that circHERC4 inactivated the tumor suppressor, miR-556-5p, leading to the activation of CTBP2/E-cadherin pathway which promotes tumor metastasis in CRC. CONCLUSIONS: CircHERC4 exerts critical roles in promoting tumor aggressiveness through miR-556-5p/CTBP2/E-cadherin pathway and is a prognostic biomarker of the disease, suggesting that circHERC4 may serve as an exploitable therapeutic target for patients with CRC.

PRMT9 promotes hepatocellular carcinoma invasion and metastasis via activating PI3K/Akt/GSK-3ß/Snail signaling.

Protein arginine methyltransferases (PRMT) catalyze protein arginine methylation and play an important role in many biological processes. Aberrant PRMT expression in tumor cells has been documented in several common cancer types; however, its precise contribution to hepatocellular carcinoma (HCC) cell invasion and metastasis is not fully understood. In this study, we identified a new oncogene, PRMT9, whose overexpression strongly promotes HCC invasion and metastasis. PRMT9 expression was detected more frequently in HCC tissues than in adjacent noncancerous tissues. PRMT9 overexpression was significantly correlated with hepatitis B virus antigen (HBsAg) status, vascular invasion, poor tumor differentiation and advanced TNM stage. Patients with higher PRMT9 expression had a shorter survival time and higher recurrence rate. PRMT9 expression was an independent and significant risk factor for survival after curative resection. Functional studies demonstrated that PRMT9 increased HCC cell invasion and lung metastasis. Knocking down PRMT9 with short hairpin RNA (shRNA) inhibited HCC cell invasion. Further investigations found that PRMT9 increased cell migration and invasion through epithelial-mesenchymal transition (EMT) by regulating Snail expression via activation of the PI3K/Akt/GSK-3ß/Snail signaling pathway. In clinical HCC samples, PRMT9 expression was positively associated with Snail expression and was negatively associated with E-cadherin expression. In conclusion, our study demonstrated that PRMT9 is an oncogene that plays an important role in HCC invasion and metastasis through EMT by regulating Snail expression via activation of the PI3K/Akt/GSK-3ß/Snail signaling pathway. Thus, PRMT9 may serve as a candidate prognostic biomarker and a potential therapeutic target.

PRMT5 promotes cell proliferation by inhibiting BTG2 expression via the ERK signaling pathway in hepatocellular carcinoma.

Increasing evidence suggests that PRMT5, a protein arginine methyltransferase, has roles in cell growth regulation and cancer development. However, the role of PRMT5 in hepatocellular carcinoma (HCC) progression remains unclear. Here, we showed that PRMT5 expression was frequently upregulated in HCC tissues, and its expression was inversely correlated with overall survival in HCC patients. PRMT5 knockdown markedly inhibited in vitro HCC proliferation and in vivo tumorigenesis. We revealed that the mechanism of PRMT5-induced proliferation was partially mediated by BTG downregulation, leading to cell cycle arrest during the G1 phase in HCC cells. Ectopic BTG2 overexpression decreased HCC growth, caused cell cycle arrest at the G1 phase, and downregulated Cyclin D1 and Cyclin E1 protein expression. Furthermore, we found that PRMT5-induced ERK phosphorylation regulated BTG2 expression in HCC cells, whereas pretreatment with a selective ERK1/2 inhibitor (PD184352) significantly reversed the effect of PRMT5 on BTG2 expression. Our results indicated that PRMT5 promotes HCC proliferation by downregulating BTG2 expression via the ERK pathway.

CCL26 Participates in the PRL-3-Induced Promotion of Colorectal Cancer Invasion by Stimulating Tumor-Associated Macrophage Infiltration.

Both phosphatase of regenerating liver-3 (PRL-3) and tumor-associated macrophages (TAM) influence cancer progression. Whether PRL-3 plays a critical role in colorectal cancer invasion and metastasis by inducing TAM infiltration remains unclear. In the current study, we investigated the effects of chemokine ligand 26 (CCL26) on TAM infiltration and colorectal cancer invasion and the underlying mechanism in colorectal cancer cells by overexpressing or silencing PRL-3. We found that PRL-3 upregulated CCL26 expression correlatively and participated in cell migration, according to the results of gene ontology analysis. In addition, IHC analysis results indicated that the PRL-3 and CCL26 levels were positively correlated and elevated in stage III and IV colorectal cancer tissues and were associated with a worse prognosis in colorectal cancer patients. Furthermore, we demonstrated that CCL26 induced TAM infiltration by CCL26 binding to the CCR3 receptor. When LoVo-P and HT29-C cells were cocultured with TAMs, CCL26 binding to the CCR3 receptor enhanced the invasiveness of LoVo-P and HT29-C cells by mobilizing intracellular Ca2+of TAMs to increase the expression of IL6 and IL8. In addition, IHC results indicated that protein levels of CCR3 and TAMs counts were higher in stage III and IV colorectal cancer tissues and correlated with CCL26. Moreover, similar results were observed in vivo using mice injected with LoVo-P and HT29-C cells. These data indicate that PRL-3 may represent a potential prognostic marker that promotes colorectal cancer invasion and metastasis by upregulating CCL26 to induce TAM infiltration. Mol Cancer Ther; 17(1); 276-89. ©2017 AACR.

PRL-3 improves colorectal cancer cell proliferation and invasion through IL-8 mediated glycolysis metabolism.

Phosphatase of regenerating liver-3 (PRL-3) has been found to be overexpressed in liver metastases of colorectal cancer and rarely expressed in primary tumors, which plays an important role in the metastasis of colorectal cancer cells. Metabolism reprogramming has been found to be a hallmark of cancer cells, and aerobic glycolysis is a metabolic adaption for cancer cells and promotes cell proliferation. However, the association between PRL-3 and glycolysis in colorectal cancer cells is not well understood. In the present study, we explored the association between PRL-3 and glycolysis. We found that PRL-3 improved colorectal cancer cell glucose assumption, lactate production and reduced intracellular ROS levels. Besides, PRL-3 improved the expression of Glut1, HK2, PKM2 and LDHA, which are important glycolysis related molecules and enzymes. Moreover, we explored IL-8 mediated enhancement of glycolysis by PRL-3. More importantly, the proliferation and invasion of colorectal cancer cells were enhanced significantly by PRL-3 through improving glycolysis. Taken together, these results implicated the important role of PRL-3 in glycolysis metabolism through improving IL-8 secretion in colorectal cancer cells, and PRL-3 mediated glycolysis contributed to the promotion of cancer metastasis.

Mitochondrial fission determines cisplatin sensitivity in tongue squamous cell carcinoma through the BRCA1-miR-593-5p-MFF axis.

Cisplatin has been widely employed as a cornerstone chemotherapy treatment for a wide spectrum of solid neoplasms; increasing tumor responsiveness to cisplatin has been a topic of interest for the past 30 years. Strong evidence has indicated that mitochondrial fission participates in the regulation of apoptosis in many diseases; however, whether mitochondrial fission regulates cisplatin sensitivity remains poorly understood. Here, we show that MFF mediated mitochondrial fission and apoptosis in tongue squamous cell carcinoma (TSCC) cells after cisplatin treatment and that miR-593-5p was downregulated in this process. miR-593-5p attenuated mitochondrial fission and cisplatin sensitivity by targeting the 3' untranslated region sequence of MFF and inhibiting its translation. In exploring the underlying mechanism of miR-593-5p downregulation, we observed that BRCA1 transactivated miR-593-5p expression and attenuated cisplatin sensitivity in vitro. The BRCA1-miR-593-5p-MFF axis also affected cisplatin sensitivity in vivo. Importantly, in a retrospective analysis of multiple centers, we further found that the BRCA1-miR-593-5p-MFF axis was significantly associated with cisplatin sensitivity and the survival of patients with TSCC. Together, our data reveal a model for mitochondrial fission regulation at the transcriptional and post-transcriptional levels; we also reveal a new pathway for BRCA1 in determining cisplatin sensitivity through the mitochondrial fission program.

[Comparison of the anti-leukemia effect and mechanism of L-asparaginase between two different strains].

This study was purposed to compare the anti-leukemic effects of E.coli-L-Asp and Erwinia-L-Asp in vitro, and to investigate their mechanism. The cell apoptosis and proliferation inhibition rate were measured by CCK-8 kit, and IC50 of two drugs was calculated by using SPSS software. Pro-apoptosis effect of E.coli-L-Asp and Erwinia-L-Asp on REH and Jurkat cell lines was also determined by flow cytometry with Annexin V/PI double staining. Concentration changes of 4 amino acids (Asn, Aspa, Gln, and Glu) before and after medication were detected by using high pressure liquid chromatography (HPLC) assay. The results showed that both REH and Jurkat cell lines were sensitive to L-Asp drugs from two different strains, and E.coli-L-Asp and Erwinia-L-Asp displayed the inhibition effect on the proliferation of Jurkat and REH cell lines in dose-dependent and time-dependent manners. The inhibition cell of proliferation and cell apoptosis in Erwinia-L-Asp group were higher than those in E.coli-L-Asp group after 24 hours (P < 0.05) . However, after treatment of REN and Jurkat cells with 2 kind of L-Asp for 48 hours, the inhibition of cell proliferation and apoptosis rates were not significantly different between the 2 L-Asp drugs (P > 0.05). The Asn in medium could be depleted by two different L-Asp drugs with low concentration. Both the two L-Asp drugs had the same capability to deplete the Asn surrounding leukemia cells (P > 0.05). The Gln in medium could be depleted by two L-Asp drugs with high concentration. The hydrolysis effect of Erwinia-L-Asp on Gln was stronger than that of E.coli-L-Asp (P < 0.05). It is concluded that in a certain range of concentrations, E.coli-L-Asp and Erwinia-L-Asp exert anti-leukemia effect in dose-dependent manner. Depletion of Gln and Asn in surrounding environment and induction of cell apoptosis are two potential mechanisms, by which leukemia cells can be killed. Erwinia-L-Asp may be chosen as the first-line drug to treat childhood ALL for its fast action and stronger hydrolysis effect on Gln.

Oncogenic function and prognostic significance of protein tyrosine phosphatase PRL-1 in hepatocellular carcinoma.

Our SNP-Chip data demonstrated 7/60 (12%) hepatocellular carcinoma (HCC) patients had PRL-1 copy number amplification. However, its biological functions and signaling pathways in HCC are deficient. Here, we investigated its oncogenic function and prognostic significance in HCC. PRL-1 protein levels were examined in 167 HCC samples by immunohistochemisty (IHC). The relationship of PRL-1 expression and clinicopathological features was assessed by correlation, Kaplan-Meier and Cox regression analyses. The oncogenic function of PRL-1 in HCC cells and its underlying mechanism were investigated by ectopic overexpression and knockdown model. PRL-1 levels in primary HCC and metastatic intravascular cancer thrombus were also determined by IHC. PRL-1 levels were frequently elevated in HCC tissues (81%), and elevated expression of PRL-1 was significantly associated with more aggressive phenotype and poorer prognosis in HCC patients (p<0.05). Ectopic overexpression of PRL-1 markedly enhanced HCC cells migration and invasion. Furthermore, the oncogenic functions of PRL-1 were mediated by PI3K/AKT/GSK3ß signaling pathway through inhibiting E-cadherin expression. Finally, PRL-1 protein levels in metastatic cancer thrombus were higher than that in primary HCC tissues (p<0.05). These data highlight the oncogenic function of PRL-1 in HCC invasion and metastasis implicating PRL-1 as a potential prognostic marker as well as therapeutic target in HCC.