Immunosuppressive Immature Myeloid Cell Generation Is Controlled by Glutamine Metabolism in Human Cancer.

Tumor-associated myeloid cells are one of the prominent components of solid tumors, serving as major immune regulators for the tumor microenvironment (TME) and an obstacle for immune-checkpoint blocking (ICB) therapy. However, it remains unclear how metabolic processes regulate the generation of suppressive myeloid cells in the TME. Here, we found that hematopoietic precursor cells are enriched in the tissues of several types of human cancer and can differentiate into immature myeloid cells (IMC). Tumor-infiltrating IMCs are highly immunosuppressive, glycolytic, and proliferative, as indicated by high levels of M-CSFR, Glut1, and Ki67. To elucidate the role of metabolism in regulating the generation of IMCs, we induced suppressive IMCs from hematopoietic precursor cells with GM-CSF and G-CSF in vitro We found that the generation of suppressive IMCs was accompanied by increased glycolysis, but not affected by glucose deprivation due to alternative catabolism. Generation of IMCs relied on glutaminolysis, regardless of glucose availability. Glutamine metabolism not only supported the expansion of IMCs with glutamine-derived α-ketoglutarate but also regulated the suppressive capacity through the glutamate-NMDA receptor axis. Moreover, inhibition of glutaminase GLS1 enhanced the therapeutic efficacy of anti-PD-L1 treatment, with reduced arginase 1+ myeloid cells, increased CD8+, IFNγ+ and granzyme B+ T cells, and delayed tumor growth in an ICB-resistant mouse model. Our work identified a novel regulatory mechanism of glutamine metabolism in controlling the generation of suppressive IMCs in the TME.

Genome-wide CRISPR knockout screens identify NCAPG as an essential oncogene for hepatocellular carcinoma tumor growth.

Hepatocellular carcinoma (HCC) is a common and deadly cancer with limited treatment options. Through genome-wide growth depletion screens using clustered regularly interspaced short palindromic repeats and expression profiling of primary HCC tumors, we identified 13 clinically relevant target genes with therapeutic potential. Subsequent functional annotation analysis revealed significant enrichment of these 13 genes in the cell cycle, cell death, and survival pathways. Non-structural maintenance of chromosomes condensin I complex subunit G (NCAPG) was ranked the highest among the depletion screens and multiple HCC expression datasets. Transient inhibition of NCAPG using specific small interfering RNAs resulted in a significant reduction in cell growth, migration, and the down-regulation of mitochondrial gene expression in vitro. Small homologous RNA-mediated knockdown of NCAPG significantly impaired cell viability, caused aberrant mitotic division, fragmented the mitochondrial network, and increased cell death in vitro. HCC cells with a reduced expression of NCAPG formed significantly smaller xenograft tumors in vivo. Importantly, high NCAPG expression was significantly associated with poorer overall and disease-free survival in HCC patients. High NCAPG expression is a novel prognostic biomarker to predict HCC early recurrence after surgical resection. In conclusion, NCAPG is an essential gene for HCC tumor cell survival. It represents a promising novel target for treating HCC and a prognostic biomarker for clinical management of HCC.-Wang, Y., Gao, B., Tan, P. Y., Handoko, Y. A., Sekar, K., Deivasigamani, A., Seshachalam, V. P., OuYang, H.-Y., Shi, M., Xie, C., Goh, B. K. P., Ooi, L. L., Hui, K. M. Genome-wide CRISPR knockout screens identify NCAPG as an essential oncogene for hepatocellular carcinoma tumor growth.

Aberrant MCT4 and GLUT1 expression is correlated with early recurrence and poor prognosis of hepatocellular carcinoma after hepatectomy.

The tumor microenvironment is a key determinant of cancer cell biology. The microenvironment is a complex mixture of tumor cells, stromal cells, and proteins, extracellular matrix, oxygen tension, and pH levels surrounding the cells that regulate the tumor progress. This study identified the prognostic factors associated with hepatocellular carcinoma (HCC) and MCT4 and GLUT1 expression levels in HCC specimens. In this study, we analyzed MCT4 and GLUT1 expression levels in tissue samples from 213 patients with HCC by immunohistochemical analyses and in HCC tumor tissues and matched adjacent nonneoplastic tissues by quantitative real-time PCR. We conducted a prognostic analysis of the overall survival (OS) and time to recurrence (TTR) using immunoreactivity and other common clinical and pathological parameters. All variables with prognostic impact were further analyzed by multivariate analysis. We found that MCT4 and GLUT1 expression levels were significantly higher in tumor tissues than in adjacent nontumor tissues, and they were positively correlated with tumor size. Survival analysis showed that patients with high expression levels of MCT4 or GLUT1 had a poor OS and TTR. In patients with HCC, MCT4 expression was an independent negative prognostic factor for OS (hazard ratio [HR] = 1.617; 95% confidence interval [CI] = 1.102-2.374; P = 0.014), and metabolic indicators were independent prognostic factors for OS (HR = 1.617, 95% CI = 1.102-2.374, P = 0.006) and TTR (HR = 1.348, 95% CI = 1.079-1.685, P = 0.009). Interestingly, patients with positive metabolic indicator expression in tumor cells had a significantly shorter OS and earlier TTR than those with negative metabolic indicator expression in tumor cells in the ≤5 cm and >5 cm subgroups. In summary, using the expression of MCT4 and GLUT1 and their metabolic parameters to determine the metabolic status of tumors is promising for predicting the prognosis of patients with HCC.

Matrix metalloproteinase 12 expression is associated with tumor FOXP3+ regulatory T cell infiltration and poor prognosis in hepatocellular carcinoma.

Hepatocellular carcinoma (HCC) is among the most fatal types of cancer worldwide due to its high rates of recurrence and metastasis. The molecular processes involved in HCC progression require further investigation to identify biomarkers for use in diagnosis and treatment. In the present study, the significance and prognostic value of matrix metallopeptidase 12 (MMP12) expression in human HCC was investigated. MMP12 mRNA expression was investigated using reverse transcription-quantitative polymerase chain reaction analysis of 42 pairs of tumor and non-tumor liver tissues obtained from patients with HCC following surgical treatment. Immunohistochemical staining was used to detect MMP12 and forkhead box P3 (FOXP3) expression in 158 paraffin-embedded HCC tissues. The prognostic value of MMP12 expression was determined using Kaplan-Meier analysis and the Cox proportional hazards model. MMP12 mRNA levels were significantly higher in liver tumor tissues compared with matched non-tumor liver tissues. MMP12 expression and FOXP3+ regulatory T cell (Treg) infiltration was positively correlated (r=0.302; P<0.001). MMP12 protein overexpression was positively correlated with tumor size (P=0.018), high serum alpha-fetoprotein levels (P=0.005) and poor overall survival time (P=0.012) in patients with HCC. Furthermore, MMP12 protein level was an independent predictive factor for overall survival time of patients with HCC who underwent curative resection. In conclusion, these results suggest that MMP12 may increase FOXP3+ Treg infiltration into tumor tissues, and promote tumor progression and immune evasion of HCC. The overexpression of MMP12 protein is, therefore, a valuable prognostic indicator in patients with HCC.

Prognostic significance of sodium-potassium ATPase regulator, FXYD3, in human hepatocellular carcinoma.

The clinical significance of the sodium-potassium ATPase regulator FXYD domain-containing ion transport regulator 3 (FXYD3) has been demonstrated in a number of types of cancer. However, the role of this protein in human hepatocellular carcinoma (HCC) remains to be elucidated. In the present study, 217 HCC tissue samples were analyzed to evaluate the expression and prognostic significance of FXYD3 in HCC. Reverse transcription-quantitative polymerase chain reaction was used to analyze the mRNA expression of FXYD3 in 80 primary HCC specimens and paired non-cancerous liver tissue samples, while western blotting was used to analyze the protein expression level of FXYD3 in another 24 pairs. These analyses demonstrated that the expression level of FXYD3 was significantly increasedb at the mRNA and protein levels in HCC tumor tissues compared with adjacent non-cancerous tissues. Immunohistochemical analysis of 137 paraffin-embedded HCC tissue samples indicated that the expression of FXYD3 was associated with HCC clinicopathological characteristics. Kaplan-Meier analysis demonstrated that patients with high FXYD3 protein expression (n=60) experienced significantly poorer overall survival time compared with patients with low FXYD3 protein expression (n=77) (P<0.001). Multivariate analysis demonstrated that FYXD3 protein expression level (hazard ratio, 2.137; 95% confidence interval, 1.224-3.732; P=0.008) was an independent prognostic factor in patients with HCC. Overall, the results indicated that FXYD3 expression levels were higher in HCC tumor tissues than in adjacent non-cancerous tissues, and that the FXYD3 protein may serve as a prognostic marker for HCC.

Optimal surgical strategy for hepatocellular carcinoma with portal vein tumor thrombus: a propensity score analysis.

OBJECTIVES: The optimal surgical resection method for hepatocellular carcinoma (HCC) patients with portal vein tumor thrombus (PVTT) that maximizes both safety and long-term outcome has not yet been determined. The aim of this study was to compare the clinical outcomes following peeling off versus en bloc resection for PVTT. METHODS: From 2005 to 2012, 252 patients with HCC and type I/II PVTT who underwent hepatic resection were divided into two groups according to whether they received en bloc resection (n = 113) or peeling off resection (n = 139). The clinical outcomes were compared before and after propensity score matching. RESULTS: The propensity model matched 113 patients with en bloc resection for further analyses. After matching, overall survival (OS) and disease-free survival (DFS) rates were significantly increased in the en bloc group compared with the peeling off group (p = 0.011 and p = 0.015). A multivariate analysis indicated that en bloc resection independently improved both OS and DFS (HR = 1.471, 95% CI: 1.071-2.018, p = 0.017 and HR = 1.415, 95% CI: 1.068-1.874, P=0.016). The adverse events were not significantly different between the two groups. However, the peeling off group showed a significantly increased recurrence rate of vascular invasion compared with the en bloc group (23.9% vs. 9.7%, p = 0.005). Similar results were also demonstrated prior to the matched analysis. CONCLUSIONS: An en bloc resection is safe and confers a survival advantage compared with a peeling off resection in HCC patients with PVTT; thus, en bloc resection should be recommended as a standard treatment for these patients when possible.

Target lesion response predicts survival of patients with hepatocellular carcinoma retreated with transarterial chemoembolization.

BACKGROUND & AIMS: The discontinuation rules of transarterial chemoembolization (TACE) for patients who were assessed as progressive disease (PD) but stage progression-free (SP-free: still belongs to Barcelona Clinic Liver Cancer B) after TACE are unclear. We aimed to evaluate the impact of the PD-pattern on the survival of these patients retreated with TACE. METHODS: In total, 115 consecutive patients who were assessed as PD but SP-free after TACE and then underwent at least one subsequent TACE session were included. Sixty patients were assessed as PD with target lesion progression (TP), and 55 patients were assessed as PD with target lesion non-progression (TNP). Survival and treatment-related adverse events were compared between the two groups. Additional external validation was performed using a data set (n = 103) from another institution. RESULTS: Patients with TNP had significantly longer median post-progression survival (PPS) than those with TP (21.0 vs. 11.9 months, P = 0.004). After TACE retreatment, the incidence of liver dysfunction was significantly higher for patients with TP than for patients with TNP (45% vs. 20%, P = 0.031). In the multivariate analysis, the target lesion response was one of the most significant prognostic factors for PPS (HR = 2.01; 95% confidence interval: 1.23-3.27; P = 0.005). The findings were supported by an independent external cohort. CONCLUSIONS: Compared to patients with TNP, patients with TP might exhibit no improvement in survival and even present damaged liver function after retreatment with TACE. Target lesion response is useful as a clinical decision for repeated TACE in these patients.

Efficacy and safety of preoperative chemoembolization for resectable hepatocellular carcinoma with portal vein invasion: a prospective comparative study.

OBJECTIVES: To evaluate the outcomes of preoperative transarterial chemoembolization (TACE) for resectable hepatocellular carcinoma (HCC) with portal vein invasion. METHODS: From February 2006 to July 2011, 320 patients initially diagnosed with resectable HCC and portal vein invasion were prospectively non-randomized into two arms. In the immediate resection arm (Arm 1, n = 205) patients received immediate surgical resection. 115 patients were included in the preoperative TACE arm (Arm 2), and eventually 85 patients underwent TACE followed by surgical resection. RESULTS: The 1-, 3- and 5-year overall survival rates were 48.3 %, 18.7 % and 13.9 % for Arm 1 and 61.2 %, 31.7 % and 25.3 % for Arm 2 (P = 0.001), respectively. In the subgroup analysis of types I and II portal vein tumour thrombus (PVTT), the preoperative TACE arm demonstrated significantly better survival rates than the immediate resection arm (P I = 0.001, P II = 0.036). However, no significant difference was found for patients with type III PVTT (P III = 0.684). No significant difference was found between the two arms in terms of complications and mortality. CONCLUSIONS: Preoperative TACE seems to confer a survival benefit for resectable HCC with PVTT, especially for types I and II PVTT, and preoperative TACE should therefore be recommended as a routine procedure. KEY POINTS: • Preoperative TACE improves the clinical outcomes for patients with PVTT • Preoperative TACE could significantly improve the rate of en bloc thrombectomy • Preoperative TACE does not increase the related adverse events.

MEP1A contributes to tumor progression and predicts poor clinical outcome in human hepatocellular carcinoma.

UNLABELLED: Although many staging classifications have been proposed for hepatocellular carcinoma (HCC), determining a patient's prognosis in clinical practice is a challenge due to the molecular diversity of HCC. We investigated the relationship between MEP1A, a candidate oncogene, and clinical outcomes of HCC patients; furthermore, we explored the role of MEP1A in HCC. In this report, it was demonstrated by quantitative real-time polymerase chain reaction that MEP1A messenger RNA levels were significantly elevated in HCC tumor tissues compared with matched adjacent nonneoplastic tissues and nonmalignant liver disease tissues. Immunohistochemical analyses of tissue samples from two independent groups of 394 HCC patients showed that positive expression of MEP1A in tumor cells was an independent and significant risk factor affecting survival after curative resection in both cohort 1 (hazard ratio = 2.05, 95% confidence interval 1.427-2.946; P < 0.001) and cohort 2 (hazard ratio = 1.89, 95% confidence interval 1.260-2.833; P = 0.002). Analysis of Barcelona Clinic Liver Cancer stage 0-A subgroup further showed that patients with positive MEP1A expression in tumor cells had poorer surgical prognoses than those with negative MEP1A expression in tumor cells (cohort 1 P = 0.001, cohort 2 P < 0.001). Both in vitro and in vivo assays showed that MEP1A promoted HCC cell proliferation, migration, and invasion. Further analyses found that MEP1A played an important role in regulating cytoskeletal events and induced epithelial-mesenchymal transition in HCC cells. CONCLUSION: MEP1A is a novel prognostic predictor in HCC and plays an important role in the development and progression of HCC.