Gut microbiota regulates the ALK5/NOX1 axis by altering glutamine metabolism to inhibit ferroptosis of intrahepatic cholangiocarcinoma cells.

Intrahepatic cholangiocarcinoma (ICC) is a kind of hepatobiliary tumor that is increasing in incidence and mortality. The gut microbiota plays a role in the onset and progression of cancer, however, the specific mechanism by which the gut microbiota acts on ICC remains unclear. In this study, feces and plasma from healthy controls and ICC patients were collected for 16S rRNA sequencing or metabolomics analysis. Gut microbiota analysis showed that gut microbiota abundance and biodiversity were altered in ICC patients compared with controls. Plasma metabolism analysis showed that the metabolite glutamine content of the ICC patient was significantly higher than that of the controls. KEGG pathway analysis showed that glutamine plays a vital role in ICC. In addition, the use of antibiotics in ICC animals further confirmed that changes in gut microbiota affect changes in glutamine. Further experiments showed that supplementation with glutamine inhibited ferroptosis and downregulated ALK5 and NOX1 expression in HuCCT1 cells. ALK5 overexpression or NOX1 overexpression increased NOX1, p53, PTGS2, ACSL4, LPCAT3, ROS, MDA and Fe2+ and decreased FTH1, SLC7A11 and GSH. Knockdown of NOX1 suppressed FIN56-induced ferroptosis. In vivo, supplementation with glutamine promoted tumor growth. Overexpression of ALK5 repressed tumor growth and induced ferroptosis in nude mice, which could be reversed by the addition of glutamine. Our results suggested that the gut microbiota altered glutamine metabolism to inhibit ferroptosis in ICC by regulating the ALK5/NOX1 axis.

Mechanism of Liver Regeneration During ALPPS.

Liver cancer is one of the most lethal malignant tumors in the world, and surgical resection is the main treatment for liver cancer. Liver failure due to insufficient residual liver volume is a fatal complication after hepatectomy. How to effectively increase the residual liver volume after hepatectomy and improve the safety of hepatectomy has always been a problem to be solved in liver surgery. Associating liver partition and portal vein ligation for staged hepatectomy (ALPPS) effectively reduces the occurrence of liver failure due to insufficient residual liver volume after hepatectomy, thereby increasing the probability of radical resection by inducing rapid proliferation of residual liver tissue. However, the molecular mechanism of residual liver tissue regeneration after primary ALPPS (combined liver partition and portal vein ligation) remains unclear. Here, we found that lots of circular RNAs (circRNAs) are upregulated after ALPPS in pig liver cells; then, we identified the orthologous circRNA in humans and pigs to detect their function in liver regeneration. The results showed that loss of circ-0067724 and circ-0016213 could suppress liver cell proliferation. Together, these findings suggest that circ-0067724 and circ-0016213 play an important role in liver cell proliferation, and this may help us to find new strategies to promote liver regeneration.

Bisphenol A regulates Snail-mediated epithelial-mesenchymal transition in hemangioma cells.

Hemangioma (HA) can be exposed to bisphenol A (BPA) through direct skin absorption. Although numerous studies indicated that BPA can trigger the progression of cancers, there is no study concerning the effects of BPA on development of HA. Our present study revealed that nanomolar BPA can significantly increase the in vitro migration and invasion of HA cells via induction of epithelial-mesenchymal transition (EMT), which was evidenced by the upregulation of vimentin and downregulation of E-cadherin. The BPA treatment also significantly increased the expression and nuclear localization of Snail and the key transcription factor of EMT, while it had no effect on the expression of other transcription factors such as Slug, Twist, or ZEB1. Silencing of Snail by small interfering RNAs attenuated BPA-induced downregulation of cadherin and upregulation of vimentin, suggesting that Snail is essential for BPA-induced EMT. Both estrogen receptor α (ERα) and G protein-coupled estrogen receptor (GPER) were expressed in HA cells; furthermore, BPA treatment can increase the expression of both ERα and GPER. However, only the inhibitor of ERα (ICI 182, 780), and not GPER (G15), can abolish BPA-induced upregulation of Snail. It suggested that ERα is involved in BPA-induced EMT of HA cells. Collectively, our data suggested that BPA can trigger the EMT of HA cells via ERα/Snail signals. It indicated that more attention should be paid to the skin exposure to BPA for HA patients.

Downregulation of miR-363 increases drug resistance in cisplatin-treated HepG2 by dysregulating Mcl-1.

Systemic therapy with cytotoxic agents provides marginal benefit in hepatocellular carcinoma (HCC) treatment especially for patients with advanced HCC. Cisplatin is one of the most active cytotoxic agents for HCC treatment. However, acquisition of cisplatin resistance is common, and one important underlying mechanism of such resistance is apoptosis-resistance. In this study, we found that miR-363 levels were significantly decreased in HCC patients treated with cisplatin-based chemotherapy. MiR-363 levels were also lower in cisplatin-resistant HepG2 (HepG2-R) cells than in HepG2 cells. Exogenous miR-363 significantly overcame cisplatin resistance in HepG2-R cells, whereas miR-363 knockdown increased the cell viability during cisplatin treatment. We further demonstrated that miR-363 directly targeted to Mcl-1 3'-UTR (3'-Untranslated Regions). Downregulation of miR-363 resulted in upregulation of Mcl-1 which is a key member of anti-apoptotic Bcl-2 family and increased drug resistance. We finally demonstrated that miR-363 decreased cisplatin resistance of HCC cell, partly by targeting Mcl-1. These data suggest that the combination of miR-363 and cisplatin may represent a novel approach in treatment for HCC, thus offering a new target for chemotherapy of HCC.

Polybutylcyanoacrylate nanoparticles as novel vectors in cancer gene therapy.

To make progress toward an efficient gene vector for cancer gene therapy, a novel nonviral vector of polybutylcyanoacrylate nanoparticles (PBCA NPs) was developed. Cetyltrimethyl ammonium bromide (CTAB) was used to modify the surface of PBCA NPs, and then the plasmid DNA (pDNA) of pAFP-TK was wrapped into PBCA-CTAB NPs. Atomic force microscopy and zeta potential demonstrated that PBCA-CTAB NPs were 80-200 nm in diameter and had +15.6 mV positive surface charges. Assay using 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide showed that PBCA-CTAB NPs had less cytotoxicity to 3T3 cells than HepG2 cells. The analysis of PBCA-CTAB-DNA complexes could not only protect DNA from degradation by DNase I, it could also transfer pDNA into targeted cells with high transfection efficiency. Furthermore, when PBCA-CTAB NPs combined with suicide gene pAFP-TK, alpha-fetoprotein-positive cells transfected by it were highly sensitive to ganciclovir treatment, and cell survival declined precipitously. Therefore, this target strategy using a pAFP-TK/GCV suicide gene therapy system in which PBCA-CTAB NPs serve as gene delivery vectors explores a promising area for alpha-fetoprotein-positive hepatocellular carcinoma and associated carcinoma therapy.

[Sentinel lymph node mapping in colorectal cancer: study of 45 cases].

OBJECTIVE: To discuss the sentinel lymph node (SLN) mapping technique in colorectal cancer and its feasibility and utility. METHODS: The dye lymphazurin was injected subserosally around the tumor during operation in 43 colorectal cancer, 20 males and 25 females, aged 49.5 (27 - 72) so as to find the SLNs. Fast-frozen pathology and routine pathology were performed too. RESULTS: SLN was successfully identified in 42 of the 45 patients, with a successful biopsy rate of 93.3%. In these 45 patients, there were 250 lymph nodes examined, of which 52 nodes were identified as SLNs. The sensitivity was 90.4% (20/22), the specificity was 95.2% [(20 + 20)/42], and the false negative rate was 15% (3/20). CONCLUSION: SLN mapping in colorectal cancer plays an important role in diagnosing metastasis of lymph nodes, and can be used to direct the clinical surgery.