C-Reactive Protein/Albumin Ratio Is an Independent Risk Factor for Recurrence and Survival Following Curative Resection of Stage I-III Colorectal Cancer in Older Patients.

BACKGROUND: The number of older patients with cancer has increased, and colorectal cancer is expected to be affected by this trend. This study aimed to compare prognostic factors, including nutritional and inflammation-based indices, between patients aged ≥ 70 and < 70 years following curative resection of stage I-III colorectal cancer. PATIENTS AND METHODS: This study included 560 patients with stage I-III colorectal cancer who underwent curative resection between May 2010 and June 2018. A retrospective analysis was performed to identify prognosis-associated variables in patients aged ≥ 70 and < 70 years. RESULTS: Preoperative low body mass index, high C-reactive protein/albumin ratio, and comorbidities were mainly associated with poor prognosis in patients aged ≥ 70 years. Tumor factors were associated with a poor prognosis in patients aged < 70 years. The C-reactive protein/albumin ratio was independently associated with poor overall survival and recurrence-free survival in those aged ≥ 70 years. The time-dependent area under the curve for the C-reactive protein/albumin ratio was superior to those of other nutritional and inflammation-based indices in most postoperative observation periods in patients aged ≥ 70 years. CONCLUSIONS: Tumor factors were associated with a poor prognosis in patients aged < 70 years. In addition to lymph node metastasis, preoperative statuses were associated with poor prognosis in patients aged ≥ 70 years. Specifically, the preoperative C-reactive protein/albumin ratio was independently associated with long-term prognosis in patients aged ≥ 70 years with stage I-III colorectal cancer after curative resection.

Weekday Surgery Associated With Short-Term Outcomes in Patients With Colorectal Cancers.

INTRODUCTION: The "weekday effect" on elective surgery remains controversial. We aimed to examine the association between the day of surgery and short-term outcomes after elective surgery for stage I-III colorectal cancer (CRC). METHODS: We performed a multicenter retrospective analysis of 2574 patients who underwent primary colorectal resection for CRC between January 2017 and December 2019 at 15 institutions belonging to the Hiroshima Surgical Study Group of Clinical Oncology. Patients were divided into two groups according to the day of surgery: Friday and non-Friday (Monday to Thursday). After propensity score matching (PSM), we compared 30-day mortality and postoperative outcomes. RESULTS: Out of the total, 368 patients underwent surgery on Fridays, and the remaining 2206 underwent surgery on non-Fridays. The overall mortality rate was 0.04% (n = 1). In 1685 patients with colon cancer, the proportion of American Society of Anesthesiologists scores was significantly lower in the Friday group than in the non-Friday group before PSM. After PSM of patient, tumor, and operative characteristics, operative time was slightly more prolonged and blood loss was slightly greater in the Friday group; however, these differences were not clinically meaningful. In the 889 patients with rectal cancer, the proportion of patients with abnormal respiratory patterns was significantly lower in the Friday group than in the non-Friday group before PSM. After PSM, the Friday group had a higher incidence of morbidity (≥ Clavien-Dindo 3a), higher incidence of digestive complications, and prolonged postoperative hospital stay. CONCLUSIONS: The results may be useful in determining the day of the week for CRC surgery, which requires more advanced techniques and higher skills.

Interleukin-33 and liver natural killer cells: A novel perspective on antitumor activity in liver fibrosis.

AIM: Liver fibrosis, heralding the potential progression to cirrhosis and hepatocellular carcinoma (HCC), compromises patient survival and augments post-hepatectomy recurrence. This study examined the detrimental effects of liver fibrosis on the antitumor functions of liver natural killer (NK) cells and the interleukin-33 (IL-33) signaling pathway. METHODS: Our investigation, anchored in both human physiologies using living and deceased donor livers and the carbon tetrachloride (CCl4)-induced mouse fibrosis model, aimed to show a troubling interface between liver fibrosis and weakened hepatic immunity. RESULTS: The Fibrosis-4 (FIB-4) index emerged as a salient, non-invasive prognostic marker, and its elevation correlated with reduced survival and heightened recurrence after HCC surgery even after propensity matching (n = 385). We established a strong correlation between liver fibrosis and liver NK cell dysfunction by developing a method for extracting liver NK cells from the liver graft perfusate. Furthermore, liver fibrosis ostensibly disrupted chemokines and promoted IL-33 expression, impeding liver NK cell antitumor activities, as evidenced in mouse models. Intriguingly, our results implicated IL-33 in diminishing the antitumor responses of NK cells. This interrelation, consistent across both mouse and human studies, coincides with clinical data suggesting that liver fibrosis predisposes patients to an increased risk of HCC recurrence. CONCLUSION: Our study revealed a critical relationship between liver fibrosis and compromised tumor immunity, emphasizing the potential interference of IL-33 with NK cell function. These insights advocate for advanced immunostimulatory therapies targeting cytokines, such as IL-33, aiming to bolster the hepatic immune response against HCC in the context of liver fibrosis.

Effect of abdominal aortic calcification on the prognosis and recurrence of colorectal cancer stages II-III: A retrospective cohort study.

PURPOSE: Abdominal aortic calcification (AAC) is a well-known risk marker for cardiovascular disease. However, its clinical effect on patients who underwent radical surgery for colorectal cancer (CRC) stages II-III is unclear. This study aimed to analyze the associations between AAC and prognosis of patients with stage II-III CRC. METHODS: To evaluate the effect of AAC on clinical outcomes, prognosis, and metastatic patterns of CRC, we analyzed 362 patients who underwent radical surgery for stage II-III CRC between 2010 and 2018. RESULTS: The high AAC group had significantly worse overall survival (OS), cancer-specific survival (CSS), and recurrence-free survival (RFS) after propensity score matching to adjust for differences in baseline characteristics of patients and tumors. In the multivariate Cox regression analyses, a high AAC was an independent risk factor for poor OS (hazard ratio [HR], 2.38; 95% confidence interval [CI], 1.23-4.59; p = 0.01), poor CSS (HR, 5.22; 95% CI, 1.74-15.6; p < 0.01), and poor RFS (HR, 1.83; 95% CI, 1.19-2.83; p < 0.01). A high AAC was not associated with a risk of lung metastasis or local or peritoneal recurrence, but a risk for liver metastasis of CRC. CONCLUSION: A high AAC showed a strong relationship with poor OS, CSS, and RFS after curative resection for stage II-III CRC. A high AAC was also associated with a risk for liver metastasis, which may worsen the prognosis in stage II-III CRC. AAC could be a new clinical tool for predicting the prognosis for patients in stage II-III CRC.

Surgery-related disseminated intravascular coagulation predicts postoperative complications.

PURPOSE: The rate of postoperative morbidity, including infectious complications, is still high after major hepatobiliary pancreatic (HBP) surgery. Although surgery-related disseminated intravascular coagulation (DIC) occurs in some cases, its significance has not been elucidated in HBP surgery. This study aimed to evaluate the influence of surgery-related DIC on the complication severity after HBP surgery. METHODS: We analyzed the records of 100 patients with hepatectomy in two or more segments, hepatectomy with biliary tract reconstruction, and pancreaticoduodenectomy. The baseline characteristics and complications were compared between patients with and without surgery-related DIC on postoperative day 1 (POD1) after HBP surgery between 2010 and 2018. Complication severity was assessed using the Comprehensive Complication Index (CCI). RESULTS: The DIC group (surgery-related DIC on POD1) had predictive factors, such as larger bleeding volume and higher liver enzyme levels. The DIC group exhibited significantly elevated rates of surgical site infection, sepsis, prolonged intensive care unit stay, more frequent blood transfusions, and higher CCI. Furthermore, compared with and without adjustment of DIC, odds ratio (OR) of AST level and operation time for  the risk of high CCI decreased (OR of AST level: 1.25 to 1.19 and OR of operation time: 1.30 to 1.23) and the significant differences had vanished. CONCLUSIONS: Surgery-related DIC on POD1 could be a partial mediator between AST level, operation time and higher CCI. The prevention or proper management of surgery-related DIC on POD1 can be an important target to reduce the severity of postoperative complications.

Adoptive immunotherapy overcomes genetic susceptibility to bloodstream infections due to fc-gamma receptor polymorphisms after liver transplantation.

Single nucleotide polymorphisms (SNPs) in FCGR3A can predict the susceptibility of liver transplant (LT) recipients to bloodstream infections (BSI) and clinical outcomes following living-donor LT (LDLT). Here, we retrospectively analyzed the relationship of adoptive immunotherapy with activated natural killer (NK) cells from perfusate effluents of liver allografts against BSI following LDLT. Higher BSI incidence and lower survival were observed in LT recipients with FcγRIIIa (158F/F or F/V) (n = 81) who did not receive adoptive immunotherapy (n = 55) than in those who did (n = 26) (BSI frequency, 36.4% vs. 11.5%; p = .033; log-rank p = .047). After matching patient background using propensity score, similar results were obtained (BSI ratio, 41.7% vs. 12.5%; p = .049; log-rank p = .039). The predominant BSI pathogens in patients who did and did not receive adoptive immunotherapy were gram-negative rods (n = 3, 100%) and gram-positive cocci (GPC) (n = 15, 65.2%), respectively. The proportion of NK cells administered to patients with BSI was significantly lower than that administered to patients without BSI (Number: 80.3 (29.9-239.2) × 106 cells vs. 37.1 (35.6-50.4) × 106 ; p = .033, percentage; 14.1 (13.3-17.8)% vs. 34.6 (16.5-47)%, p = .0078). Therefore, adoptive immunotherapy with NK cells was associated with the reduced post-transplant BSI related to GPCs due to FcγRIIIa SNP in LT recipients.

Acute diffuse thyroid swelling after fine-needle aspiration: A case report and review of the literature.

Fine-needle aspiration (FNA) is the first-line and a cost-effective examination method of nonfunctional thyroid nodules. Acute transient thyroid swelling after an FNA is a rare complication, and to date, only 14 cases have been reported in the English literature. Herein, we report a case of a 26-year-old woman with acute transient thyroid swelling, which occurred after an ultrasound-guided FNA of a thyroid nodule. Although the patient had undergone an FNA without complication 2 years previously, the second FNA caused acute thyroid swelling. The present case emphasizes the potential risk of acute thyroid swelling associated with every FNA procedure.

Association of Abdominal Aortic Calcification With the Postoperative Metabolic Syndrome Components After Liver Transplantation.

BACKGROUND: This study aimed to assess the risk factors for components of metabolic syndrome, such as diabetes mellitus, hypertension, and dyslipidemia, more than a year after liver transplantation. METHODS: This study included 164 patients with liver failure secondary to acute and chronic liver disease or hepatocellular carcinoma who underwent liver transplantation between 2000 and 2019. Univariate and multivariate analyses were performed to identify the risk factors associated with metabolic syndrome components after liver transplantation. RESULTS: The median follow-up period was 10.5 years. Of the 164 patients who underwent liver transplantation, 144 (87.8%) developed components of metabolic syndrome after liver transplantation. The most common cause of liver failure was hepatitis C virus infection (34.1%). The incidence of hepatocellular carcinoma was 36.0%. In univariate analysis, preoperative diabetes mellitus was a significantly more common component of metabolic syndrome than the others. In multivariate analysis, preoperative abdominal aortic calcification was a risk factor for the new onset of all components of metabolic syndrome after liver transplantation, despite the varying degree of calcification at risk of development (odds ratio for diabetes mellitus = 3.487, P = .0069; odds ratio for hypertension = 2.914, P = .0471; odds ratio for dyslipidemia = 3.553, P = .0030). CONCLUSIONS: Preoperative abdominal aortic calcification was significantly associated with the development of each metabolic syndrome component after liver transplantation.

Atherosclerosis Deteriorates Liver Ischemia/Reperfusion Injury Via Interferon Regulatory Factor-1 Overexpression in a Murine Model.

BACKGROUND: Abdominal aortic calcification (AAC) is associated with cardiovascular-related mortality, along with an elevated risk of coronary, cerebrovascular, and cardiovascular events. Notably, AAC is strongly associated with poor overall and recurrence free survival posthepatectomy for hepatocellular carcinoma. Despite the acknowledged significance of atherosclerosis in systemic inflammation, its response to ischemia/reperfusion injury (IRI) remains poorly elucidated. In this study, we aimed to clarify the impact of atherosclerosis on the liver immune system using a warm IRI mouse model. METHODS: Injury was induced in an atherosclerotic mouse model (ApoE-/-) or C57BL/6J wild-type (WT) mice through 70% clamping for 1 hour and analyzed after 6 hours of reperfusion. RESULTS: Elevated serum levels of aspartate and alanine aminotransferase, along with histological assessment, indicated considerable damage in the livers of ApoE-/- mice than that in WT mice. This indicates a substantial contribution of atherosclerosis to IRI. Furthermore, T and natural killer (NK) cells in ApoE-/- mouse livers displayed a more inflammatory phenotype than those in WT mouse livers. Reverse transcription-polymerase chain reaction analysis revealed a significant upregulation of interleukin (IL)-15 and its transcriptional regulator, interferon regulatory factor-1 (IRF-1) in ApoE-/- mouse livers compared with that in WT mouse livers. CONCLUSIONS: These findings suggest that in an atherosclerotic mouse model, atherosclerosis can mirror intrahepatic immunity, particularly activating liver NK and T cells through IL-15 production, thereby exacerbating hepatic damage. The upregulation of IL-15 expression is associated with IRF-1 overexpression.

Donor Age Correlates With Liver-Resident Natural Killer Cell Activity in Adoptive Immunotherapy Using Donor Liver Natural Killer Cells in Liver Transplantation.

BACKGROUND: Natural killer (NK) cells are involved in innate immunity and have been reported to play an important role in hepatocellular carcinoma recurrence and post-liver transplantation (LT) infection. However, the relationship between donor age and liver-resident NK cell activity remains to be elucidated. METHODS: We successfully performed NK cell immunotherapy in 19 living donor LT recipients to prevent post-LT bloodstream infections. Liver mononuclear cells (LMNCs) were collected from the liver graft perfusate and stimulated with interleukin 2 for 3 days. Liver-resident NK cells were analyzed using flow cytometry and a chromium release assay before and after cell culture. RESULTS: The median donor age was 44 years (range, 24-64 years). The graft weight was 492 g (range, 338-642 g), and the median number of LMNCs was 584 million cells (range, 240-1472 million cells). The proportion of NK cells before and after culture was 22% and 33%, respectively. A significant correlation was found between graft weight and the number of LMNCs. However, no correlation was found between donor age and the number or percentage of NK cells in the liver. Moreover, donor age showed a significant inverse correlation with NKp46 and NKp44 expression before culture and with NKp44, tumor necrosis factor-related apoptosis-inducing ligand, and CD69 expression after culture. CONCLUSION: A significant inverse correlation was observed between donor age and NK cell activity in the liver. This information may be useful for cell therapy during LT.

Immunotherapy Using Activated Natural Killer Cells Improves Postoperative Neutrophil-to-Lymphocyte Ratio and Long-Term Prognosis of Living Donor Liver Transplant Recipients With Hepatocellular Carcinoma.

OBJECTIVE: Preoperative neutrophil-to-lymphocyte ratio (NLR) is a well-known prognostic indicator in various malignancies; however, the impact of postoperative NLR on living donor liver transplant (LDLT) recipients is unknown. Immunotherapy with donor liver-derived activated natural killer (NK) cells may improve postoperative NLR by coactivating immune cells or suppressing activated neutrophils. This study aims to clarify the clinical significance of postoperative NLR in recipients after LDLT with HCC and assess whether immunotherapy improves postoperative NLR. METHODS: We conducted a retrospective study of LDLT recipients between 2001 and 2022 to evaluate the clinical significance of postoperative NLR. Furthermore, the correlation between postoperative NLR and the activation marker of infused NK cells was also evaluated. The postoperative NLR was examined 4 weeks after LDLT. RESULTS: The postoperative high NLR group (N = 78) had preoperative lower NLR and higher model for end-stage liver disease and a higher rate of postoperative infection within 30 days after LDLT than the postoperative low NLR group (N = 41). Postoperative high NLR (hazard ratio [HR], 2.62; 95% confidence interval [CI], 1.01-6.79; P = .047) and nontreatment of immunotherapy (HR, 3.10; 95% CI, 1.33-7.22; P < .01) were independent risk factors for poor overall survival in multivariate analysis. Furthermore, the activation marker of infused NK cells is inversely correlated with decreased postoperative NLR. CONCLUSIONS: The higher level of postoperative NLR was independently associated with poor prognosis in patients after LDLT with HCC. Immunotherapy using activated NK cells may improve postoperative NLR and long-term prognosis.

Impact of a Liver Immune Status Index among Living Liver Transplant Recipients with Hepatocellular Carcinoma.

Introduction: Hepatocellular carcinoma (HCC) is a major global health challenge, being the fifth most prevalent neoplasm and the third leading cause of cancer-related deaths worldwide. Liver transplantation offers a potentially curative approach for HCC, yet the risk of recurrence posttransplantation remains a significant concern. This study investigates the influence of a liver immune status index (LISI) on the prognosis of patients undergoing living-donor liver transplantation for HCC. Methods: In a single-center study spanning from 2001 to 2020, 113 patients undergoing living-donor liver transplantation for HCC were analyzed. LISI was calculated for each donor liver using body mass index, serum albumin levels, and the fibrosis-4 index. This study assessed the impact of donor LISI on short-term recurrence rates and survival, with special attention to its correlation with the antitumor activity of natural killer (NK) cells in the liver. Results: The patients were divided into two grades (high donor LISI, >-1.23 [n = 43]; and low donor LISI, ≤-1.23 [n = 70]). After propensity matching to adjust the background of recipient factors, the survival rates at 1 and 3 years were 92.6% and 88.9% and 81.5% and 70.4% in the low and high donor LISI groups, respectively (p = 0.11). The 1- and 3-year recurrence-free survival were 88.9% and 85.2% and 74.1% and 55.1% in the low and high donor LISI groups, respectively (p = 0.02). Conclusions: This study underscores the potential of an LISI as a noninvasive biomarker for assessing liver NK cell antitumor capacity, with implications for living-donor liver transplantation for HCC. Donor LISI emerges as a significant predictor of early recurrence risk following living-donor liver transplantation for HCC, highlighting the role of the liver antitumor activity of liver NK cells in managing liver malignancies.

Effect of Abdominal Aortic Calcification on Recurrence Following Initial Hepatectomy for Colorectal Liver Metastases.

BACKGROUND/AIM: The aim of the study was to analyze the association between abdominal aortic calcification (AAC) and patient prognosis following resection of colorectal liver metastases (CRLM). AAC potentially reflects intrahepatic immunity and is involved in tumor development and progression. However, the clinical effects of AAC on colorectal cancer (CRC) prognosis after curative-intent liver resection for CRLM remain unclear. PATIENTS AND METHODS: We evaluated the effect of AAC on the clinical prognosis and metastatic patterns in 99 patients who underwent hepatectomy for CRLM between 2010 and 2019. RESULTS: The high-AAC group had significantly worse overall survival (OS) and remnant liver recurrence rate (RR) after propensity score matching to adjust for differences in baseline characteristics of patients and tumors. In multivariate Cox regression analyses, high AAC volume was an independent risk factor for poor OS and liver RR, but not poor lung RR. The expression of tumor necrosis factor-related apoptosis-inducing ligand, known as an anti-tumor marker, in liver natural killer (NK) cells was lower in the high-AAC group than in the low-AAC group. CONCLUSION: High AAC volume showed a strong relationship with remnant liver RR after curative resection of CRLM. High AAC volume may be responsible for the suppression of anti-tumor activity of liver NK cells, which results in an increased risk of liver recurrence and poor prognosis.

The aryl hydrocarbon receptor maintains antitumor activity of liver resident natural killer cells after partial hepatectomy in C57BL/6J mice.

BACKGROUND: Liver-resident natural killer (lr-NK) cells are distinct from conventional NK cells and exhibit higher cytotoxicity against hepatoma via tumor necrosis factor-related apoptosis-inducing ligand (TRAIL). However, the mechanism by which partial hepatectomy (PH) significantly suppresses TRAIL expression in lr-NK cells remains unclear. METHODS: This study aimed to investigate the PH influence on the function and characteristics of liver-resident NK (lr-NK) cells using a PH mouse model. RESULTS: Here, we report that PH alters the differentiation pattern of NK cells in the liver, and an aryl hydrocarbon receptor (AhR) molecule is involved in these changes. Treatment with the AhR agonist 6-formylindolo[3,2-b]carbazole (FICZ) inhibited the maturation of NK cells. FICZ increased the immature subtype proportion of NK cells with high TRAIL activity and decreased the mature subtype of NK cells with low TRAIL activity. Consequently, FICZ increased the expression of TRAIL and cytotoxic activity of NK cells in the liver, and this effect was confirmed even after hepatectomy. The participation of AhR promoted FoxO1 expression in the mTOR signaling pathway involved in the maturation of NK cells, resulting in TRAIL expression. CONCLUSION: Our findings provide direct in-vivo evidence that partial hepatectomy affects lrNK cell activity through NK cell differentiation in the liver. Perioperative therapies using an AhR agonist to improve NK cell function may reduce the recurrence of hepatocellular carcinoma after hepatectomy.

Preoperative endoscopic tattoo marking improves lymph node retrieval in laparoscopic rectal resection: a retrospective cohort study.

PURPOSE: Harvesting at least 12 lymph nodes (LNs) is recommended for adequate tumor staging in colon surgery. Although preoperative endoscopic tattooing has been used for primary localization of tumors, its impact on LN retrieval in colorectal surgery remains controversial. We aimed to investigate the relationship between preoperative tattooing and LN retrieval after laparoscopic rectal resection. METHODS: We reviewed the records of 92 patients with rectal cancer who underwent laparoscopic resection from January 1, 2018 to December 31, 2019. Patients were categorized into 2 groups according to whether preoperative endoscopic tattooing was performed. The rate of adequate LN retrieval (≥12) was compared. RESULTS: The tattooed and non-tattooed groups comprised 49 and 43 patients, respectively. In the tattooed and non-tattooed groups, the rates of adequate LN retrieval were 75.5% and 55.8%, respectively (P=0.046). Univariate analysis revealed that female sex, tattooing, LN metastasis status, pathological pathological stage (p-stage), and LN dissection were predictive factors for adequate LN retrieval. In the multivariate analysis, female sex (odds ratio [OR], 3.34; 95% confidence interval [CI], 1.15-9.73; P=0.027), tattooing (OR, 2.87; 95% CI, 1.03-7.94; P=0.043), and p-stage (OR, 3.34; 95% CI, 1.04-10.75; P=0.043) were independent predictive factors for adequate LN retrieval after surgery. CONCLUSION: This study revealed that preoperative endoscopic tattooing was statistically significantly associated with adequate LN retrieval in patients with rectal cancer who underwent laparoscopic rectal resection. Preoperative endoscopic tattooing should be considered to improve disease assessment and avoid stage migration.

Arteriosclerosis Decreases Tumor Necrosis Factor-Related Apoptosis-Inducing Ligand Expression on Liver Natural Killer Cells in Living Donor Liver Transplantation.

BACKGROUND: Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) is critical for natural killer (NK) cell-mediated anti-tumor and anti-microbe killing. The TRAIL expression on the donor's liver NK cells from the liver perfusate after interleukin-2 stimulation varies between individuals and is unpredictable. This study aimed to clarify the risk factors for low TRAIL expression by analyzing perioperative donor characteristics. METHODS: This retrospective study of living donor liver transplant (LDLT) donors between 2006 and 2022 was performed to analyze low TRAIL expression risk factors. Seventy-five donors who had undergone hepatectomy for LDLT were divided into 2 groups, low and high TRAIL, according to their TRAIL expression on liver NK cells, using median values. RESULTS: The low TRAIL group (N = 38) was older and had lower nutrition and a higher low-density lipoprotein/high-density lipoprotein (LDL/HDL) cholesterol ratio, related to arteriosclerosis, than the high TRAIL group (N = 37). In multivariate analysis, the geriatric nutritional risk index (GNRI) (odds ratio, 0.86; 95% CI, 0.76-0.94; P < .001) and LDL/HDL cholesterol ratio (odds ratio, 2.32; 95% CI, 1.10-4.86; P = .005) were independent predictive factors for low TRAIL expression on liver NK cells. Furthermore, the TRAIL expression of liver NK cells decreased in donors who already had atherosclerosis and in donors at risk of potentially developing atherosclerosis. CONCLUSIONS: The TRAIL expression on liver NK cells in donors had a strong relationship with atherosclerosis and GNRI. Atherosclerosis can reflect the TRAIL expression on liver NK cells.

Impact of a new liver immune status index among patients with hepatocellular carcinoma after initial hepatectomy.

Aim: The anti-tumor effects of natural killer (NK) cells vary among individuals. Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) expressed on liver NK cells is a marker of anti-tumor cytotoxicity against hepatocellular carcinoma (HCC) in immune cell therapy. This study aimed to develop a liver immune status index (LISI) that predicts low TRAIL expression and validates its ability to predict recurrence after initial hepatectomy for primary HCC. Methods: A functional analysis of liver NK cells co-cultured with interleukin-2 for 3 days was performed of 40 liver transplant donors. The LISI, which predicted low TRAIL expression (25% quartile: <33%) in liver NK cells, was calculated using multiple logistic regression analysis. Next, 586 initial hepatectomy cases were analyzed based on the LISI. Results: Our model was based on the Fibrosis-4 index+0.1 (odds ratio [OR], 1.33), body mass index (OR, 0.61), and albumin levels+0.1 (OR, 0.54). The area under the receiver operating characteristic curve (AUC) of the LISI for low TRAIL expression was 0.89. Stratification of the recurrence rates (RR) revealed that LISI was an independent predictive factor of RR (moderate risk: hazard ratio, 1.44; high risk: hazard ratio, 3.02). The AUC was similar for the LISI, albumin-indocyanine green evaluation grade, albumin-bilirubin score, and geriatric nutritional risk index for predicting RR. Among the vascular invasion cases, the LISI was more useful than the other indexes. Conclusion: Our model facilitates the prediction of RR in high-risk patients by providing LISI to predict the anti-tumor effects of NK cells.

Acute portal hypertension using portal vein ligation abrogates TRAIL expression of liver-resident NK cells.

The effects of acute portal hypertension (PHT), which is reported as poor prognostic factors in patients with hepatocellular carcinoma, are not well known on the liver immune system, including natural killer (NK) cells. The aim of this study, therefore, was to investigate how acute PHT influences the functions and characteristics of liver-resident NK (lr-NK) cells using an acute PHT mouse model. Acute PHT decreased the number of tumor necrosis factor-related apoptosis-inducing ligand (TRAIL+ ) lr-NK cells by about 20% and attenuated cytotoxic activity against the Hepa1-6 cell line by about 40%. Among various cytokine, only interleukin-33 (IL-33), which inhibits NK activity, significantly increased after portal vein ligation (PVL). Because lr-NK cells highly expressed ST2/IL-33R, IL-33 co-culture significantly suppressed TRAIL expression on lr-NK cells by about 50%, and IL-33 administration markedly decreased TRAIL expression and cytotoxic activity of lr-NK cells. Furthermore, the TRAIL+ NK cells population was maintained by anti-IL33 antibody or following portosystemic shunt procedure even after PVL. Finally, we demonstrated that IL-33 decreased TRAIL expression in lr-NK cells via AKT-forkhead box O (FoxO) and mitogen-activated protein kinase (MAPK) signaling. Conclusion: This work demonstrates that PHT suppresses the TRAIL+ lr-NK cell population and antitumor activities in the liver. Additionally, Akt-FoxO and MAPK signaling pathways attenuate the TRAIL expression in lt-NK cells via IL-33 receptor in mice.