Diverse Alterations of Glomerular Capillary Networks in Focal Segmental Glomerular Sclerosis.

Introduction: Focal segmental glomerular sclerosis (FSGS) is caused by podocyte injury. It is characterized by obliteration of glomerular capillary tufts with increased extracellular matrix (ECM). Altered communication between podocytes and glomerular endothelial cells (ECs) contributes to sclerosis progression. We focused on EC injury in the FSGS. Methods: A total of 29 FSGS and 18 control biopsy specimens were assessed for clinicopathologic characteristics. CD34 (a marker for EC)-positive capillaries and ECM accumulation were evaluated quantitatively for each variant using computer-assisted image analysis. Results: The estimated glomerular filtration rate (eGFR) in the FSGS group was significantly lower than that in the control group. The frequency of FSGS variants was 51.7% for cellular; 13.8% for perihilar (PH), tip, and not otherwise specified (NOS); and 6.9% for collapsing. Regarding sclerotic lesions in all FSGS, narrowing or loss of CD34-positive capillaries was observed. Electron microscopy results showed loss of fenestrae, subendothelial space enlargement, and cytoplasmic swelling, indicating EC injury. Computer-assisted image analysis revealed significantly smaller areas of glomerular capillaries in FSGS with or without sclerotic lesions, with increased ECM. Moreover, in comparison with each variant, narrowed capillaries and ECM accumulation were most prominent in the collapsing variant, whereas the tip variant had the least change. Conclusion: EC injury was observed in all FSGS cases, not only in sclerotic lesions but also in nonsclerotic lesions. Severity of EC injury may vary in each variant due to diverse alterations of glomerular capillary networks.

Value of the CRP-albumin ratio in patients with resectable pancreatic cancer.

Background : The C-reactive protein (CRP)-albumin ratio (CAR) was reported as a prognostic factor of resectable hepatocellular carcinoma. The aim of this study was to analyse the significance of CAR in resectable pancreatic cancer. Patients and Methods : 163 patients with curative resection for pancreatic cancer were enrolled in this retrospective study. Cases of non-curative resection were excluded. The CAR was calculated with the preoperative plasma CRP and albumin values, with a cut-off value of 0.06, as calculated in a previous report. Results : Patients in the low CAR group had significantly better overall survival (OS) and disease-free survival (DFS) compared with the high CAR group (P < 0.05). On multivariate analysis, for high CAR, CA19-9 > 300 U / ml and receipt of adjuvant chemotherapy were independent risk factors for OS and DFS. High CAR was significantly associated with advanced T stage. Conclusion : The CAR might be a prognostic factor for patients with resectable pancreatic cancer. J. Med. Invest. 68 : 244-248, August, 2021.

Value of the fibrinogen-platelet ratio in patients with resectable pancreatic cancer.

Background : Several prognostic factors were reported in pancreatic cancer. The fibrinogen-platelet ratio (FPR) was reported as a prognostic factor of resectable gastric cancer. In this report, the FPR was evaluated in patients with resectable pancreatic cancer. Methods : Between 2004 and 2019, 163 patients with curative resection for pancreatic cancer were enrolled. Cases of non-curative resection were excluded. The FPR was calculated using the preoperative plasma fibrinogen and the platelet counts and the cut-off value was determined by receiver operating characteristic (ROC) curve analysis. The patients were divided into high and low FPR groups according to this cut-off value. Results : The cut-off value of FPR was 25.2. Among age, sex, body mass index (BMI), and surgical factors including surgery type, volume of blood loss and surgery time, there was no significant difference between the two groups. Patients in the low FPR group had significantly better overall survival (OS) and relapse-free survival (RFS) compared with the high FPR group (P < 0.05). On multivariate analysis, a high FPR, CA19-9 > 300 U / ml, and receipt of adjuvant chemotherapy were independent risk factors for OS and DFS. Conclusions : The FPR might be a prognostic factor for patients with resectable pancreatic cancer. J. Med. Invest. 68 : 342-346, August, 2021.

Prognostic prediction of resectable colorectal liver metastasis using the apparent diffusion coefficient from diffusion-weighted magnetic resonance imaging.

AIM: Diffusion-weighted magnetic resonance imaging (DWI-MRI) is used to predict tumor malignancy. Here we explored the role of apparent diffusion coefficient (ADC) values in the treatment of patients with resectable colorectal liver metastasis (CRLM). METHODS: Magnetic resonance imaging (MRI) scans were conducted using a Signa HDe or Signa Explorer 1.5-T scanner (GE Healthcare). ADC maps were calculated using DWI with b values of 0, 20, and 800 s/mm2. We enrolled 60 patients who underwent upfront hepatic resection for CRLM and divided them into ADC-high (n = 30) and ADC-low (n = 30) groups. Clinicopathological variables of the groups were compared. Immunohistochemical analysis of HIF-1α expression in tumor tissues was performed, and the relationship between the ADC value and HIF-1α expression was evaluated. RESULTS: The disease-free survival rate of the ADC-low group was significantly lower than that of the ADC-high group (P < .05). Univariate analysis revealed that tumor number (more than five), synchronous metastasis, and low ADC were prognostic factors. Multivariate analysis identified low ADC as an independent prognostic factor. Furthermore, the ADC-low group more frequently expressed high levels of HIF-1α than the ADC-high group. CONCLUSION: Low ADC values were an independent prognostic factor of resectable CRLM and correlated with HIF-1α expression.

Immunohistochemical detection of citrullinated histone H3-positive neutrophils is useful for identifying active glomerular and interstitial lesions in antineutrophil cytoplasmic antibody-associated vasculitis.

AIMS: Activated neutrophils release neutrophil extracellular traps (NETs), resulting in a form of cell death called NETosis. NET formation is reportedly involved in the onset of systemic lupus erythematosus and antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV). Citrullination of histones is a key step in NET formation, and the presence of citrullinated histones in neutrophils may be associated with disease induction and activity. The aim of this study was to investigate the relationship between infiltrating citrullinated histone H3 (H3Cit)-positive neutrophils and disease specificity and activity in various glomerulonephritides. METHODS AND RESULTS: We selected 32 kidney biopsies with glomerulonephritides, including AAV, lupus nephritis (LN), Henoch-Schönlein purpura nephritis (HSPN), and poststreptococcal acute glomerulonephritis (PSAGN). We examined the presence of H3Cit in infiltrating neutrophils and their association with necrotising, crescentic lesions and tubulointerstitial lesions. In PSAGN and HSPN, we found many myeloperoxidase (MPO)+ neutrophils in glomeruli; however, only a few were H3Cit+. In LN, MPO+ neutrophils mainly existed in the margins of glomerular tufts forming wire-loop lesions, and some of these were noted to be H3Cit+ neutrophils. In contrast, we found a significantly higher frequency of H3Cit+ neutrophils, despite the small number of MPO+ neutrophils, in microscopic polyangiitis in AAV. In particular, H3Cit+ neutrophils were prominent in necrotising lesions along the glomerular capillaries. Moreover, we also found H3Cit+ neutrophils in the interstitium, with marked peritubular capillaritis in AAV. CONCLUSIONS: H3Cit immunostaining is a useful tool for identifying activated neutrophils. The frequency of H3Cit+ neutrophils is not only a disease-specific marker but also a potential marker for disease activity in AAV.

Significance of Frailty in Prognosis After Hepatectomy for Elderly Patients with Hepatocellular Carcinoma.

BACKGROUND: The concept of frailty becomes important for patients who undergo surgery in this recent aging society. The aim of this study is to investigate the frailty as a prognostic factor in elderly patients with hepatocellular carcinoma (HCC) who underwent hepatectomy. PATIENTS AND METHODS: A total of 92 patients over 75 years old who underwent hepatectomy were enrolled in this study. Frailty was defined as clinical frailty scale (CFS) ≥ 4. Patients were divided into two groups, i.e., frailty group (n = 21) and no-frailty group (n = 71), and clinicopathological features were compared between them. RESULTS: The frailty group showed significant higher PIVKA-II level and larger tumor diameter (p < 0.05). CRP level and modified Glasgow prognostic score were significantly higher in the frailty group (p < 0.05). The frailty group showed higher rate of postoperative complications of Clavien-Dindo III (p = 0.06) and longer postoperative stay (p = 0.08). Cancer-specific, overall, and disease-free survival rates were significantly worse in the frailty group (p < 0.05). Frailty was detected as an independent prognostic factor on multivariate analysis of cancer-specific survival. CONCLUSION: Frailty can estimate the prognosis of HCC patients who underwent hepatectomy.

Prognostic prediction of apparent diffusion coefficient obtained by diffusion-weighted MRI in mass-forming intrahepatic cholangiocarcinoma.

BACKGROUND: We evaluated apparent diffusion coefficient (ADC) of diffusion-weighted image MRI as a prognostic factor for mass-forming intrahepatic cholangiocarcinoma (IHCC). METHODS: We enrolled 26 patients who had undergone hepatic resections for mass-forming-type IHCC in this study, and calculated their mean ADC, using diffusion-weighted image MRI (b: 0, 20, 800 seconds/mm2 ; 1.5 T MRI). Patients were divided into the ADCHigh and the ADCLow groups at the median ADC value (n = 13 for both). We also immunohistochemically evaluated hypoxia-inducible factor (HIF)-1α in tumor tissue. RESULTS: Median age in the ADCLow was older (P = .03), and showed significant higher rate of scirrhous tumor (P = .02). The 5-year overall survival rate in the ADCLow group was significantly worse than in the ADCHigh group (P = .04). In multivariate analysis, hilar tumor, portal vein invasion and low ADC were independent prognostic factors (P < .05). The ADCLow group also had a higher rate of high HIF-1α expression than the ADCHigh group (P < .05). Representative case of ADCLow group showed rich stroma and high HIF-1α expression. CONCLUSIONS: The ADC values in MRIs can predict IHCC prognosis, and correlated with stromal density and HIF-1α expression.

Carbohydrate Antigen 19-9 Is a Prognostic Factor Which Correlates With HDAC1 and HIF-1α for Intrahepatic Cholangiocarcinoma.

BACKGROUND/AIM: Carbohydrate antigen 19-9 (CA19-9) is a poor prognostic marker in intrahepatic cholangiocarcinoma (IHCC). Previous studies have shown a link between hypoxia and CA19-9 in cancer, and we have previously demonstrated a correlation between HDAC1 and HIF-1α in IHCC. Here, we evaluated the expression and correlation of CA19-9 with HIF-1 and HDAC in IHCC. PATIENTS AND METHODS: This study included 62 patients with IHCC who underwent primary hepatectomy at our department. Clinicopathological characteristics were examined. Immunohistochemical expression of HIF-1 and HDAC1 in specimens was quantitatively evaluated. RESULTS: Patients with high preoperative serum CA19-9 levels showed clinicopathological characteristics associated with tumour progression. High CA19-9 levels were associated with worse overall and recurrence-free survival. Univariate and multivariate analysis detected high CA19-9 levels as an independent poor prognostic factor for IHCC. Serum CA19-9 was significantly correlated with both HIF-1α and HDAC1 expression. CONCLUSION: High serum CA19-9 level is a poor prognostic factor for overall survival in IHCC and correlates with HIF-1α and HDAC1 expression.

Influence of renal ischaemia-reperfusion injury on renal neutrophil gelatinase-associated lipocalin receptor (24p3R) in rats.

The neutrophil gelatinase-associated lipocalin (NGAL) receptor (24p3R) is expressed in distal nephron and contributes to the endocytosis of NGAL in urine. This study was undertaken to evaluate an influence of renal ischaemia-reperfusion injury on 24p3R. Unilateral renal pedicle was clamped for 0, 10, 20, 30, or 45 minutes in male Wistar rats. Urine was collected for 24 hours after reperfusion, and ischaemic kidney and blood sample were obtained. Apparent histological injury in the ischaemic kidney was detected in the 30 and 45 minutes-treated groups. Urinary NGAL excretion elevated in rats with renal ischaemia for more than 20 minutes, while serum creatinine increased in rats for more than 30 minutes of ischaemia. Renal protein expression of NGAL did not significantly change. Renal mRNA expressions of megalin and cubilin, which are expressed at renal proximal tubules and uptake NGAL, decreased in animals with renal ischaemia for more than 20 minutes. Renal protein expression of 24p3R, which is expressed at renal distal tubules and uptake NGAL, decreased in rats with renal ischaemia for 45 min. This study showed for the first time that renal 24p3R decreased in response to renal ischaemia. As relatively longer renal ischaemia (45 minutes) decreased renal 24p3R protein and increased urinary NGAL excretion, the down-regulation of 24p3R protein might contribute to the elevated urinary excretion of NGAL in rats with unilateral ischaemia-reperfusion injury.

Overexpression of IGF2 and IGF2 receptor in malignant solitary fibrous tumor with hypoglycemia: a case report.

BACKGROUND: Solitary fibrous tumor (SFT) is a prototypical mesenchymal neoplasm that induces non-islet cell tumor hypoglycemia (NICTH) due to overproduction of insulin-like growth factor 2 (IGF2). We here report the case of a malignant SFT associated with a hypoglycemia attack. CASE PRESENTATION: An 81-year-old man with a large subphrenic mass presented with hypoglycemia and loss of consciousness. His serum insulin and IGF1 levels were relatively low, suggesting an excessively high serum IGF2 levels. Preoperative Western blotting of serum confirmed the overproduction of high-molecular-weight IGF2. After total tumor resection, the patient recovered from hypoglycemia without the need for further treatment. Histological examination revealed proliferation of spindle cells and frequent nuclear mitoses with STAT6 and CD34 immunoreactivity, which led to the diagnosis of malignant SFT. IGF2 was strongly upregulated in the tumor upon immunohistochemistry, consistent with the report of NICTH. In addition, the tumor expressed IGF2 receptor (IGF2R) but not IGF1R. CONCLUSIONS: The present results indicate that the tumor co-expressed IGF2 and IGF2R. IGF2R has not previously been recognized as a tyrosine kinase receptor participating in cell signal transduction. Thus, further case series are required to determine whether IGF2R overexpression reflects the action of an unknown autocrine/paracrine system involving IGF2 for cell proliferation or for the scavenging and degradation of IGF2.

The Outcome of Sorafenib Therapy on Unresectable Hepatocellular Carcinoma: Experience of Conversion and Salvage Hepatectomy.

BACKGROUND/AIM: We report the outcomes of sorafenib therapy for advanced hepatocellular carcinoma (HCC) in our Department. PATIENTS AND METHODS: Thirty-eight patients with unresectable HCC who were administrated sorafenib from 2009 to 2015 were investigated retrospectively. RESULTS: The 1-year overall survival rate was 59.3%. The macroscopic vascular invasion and response rate were independent prognostic factors of survival. Surgical resection after sorafenib achieved long-term survival in two cases. Case 1: A patient with locally unresectable HCC showed significant response induced by sorafenib, which allowed complete surgical resection. This tumor tested positive for FGF4. Case 2: A patient with a history of hepatectomy for HCC had multiple distant metastases. Most lesions were reduced in size after sorafenib therapy and new lesions in the remnant liver and residual lung metastases were resected. The sorafenib-resistant lesions were negative for FGF4. CONCLUSION: Sorafenib combined with surgical resection is a feasible option in advanced HCC patients, if sorafenib has been effective.

Effect of Adjuvant Gemcitabine Combined with Low-dose 5-Fluorouracil and Cisplatin Chemotherapy for Advanced Biliary Carcinoma.

BACKGROUND/AIM: The aim of this retrospective study was to clarify the effectiveness of chemotherapy with gemcitabine combined with low-dose 5-fluorouracil and cisplatin (GFP) for advanced biliary carcinoma after hepatectomy. PATIENTS AND METHODS: Sixty-two patients had biliary carcinoma with lymph node metastasis, intrahepatic metastasis or positive surgical margins, including intrahepatic cholangiocarcinoma (IHC, n=25), hilar cholangiocarcinoma (HC, n=14), and gallbladder cancer (GBC, n=23). Twenty-eight patients (IHC; n=9, HC; n=8, GBC; n=11) received adjuvant GFP chemotherapy. RESULTS: We found no significant difference in clinicopathological factors in patients treated with or without adjuvant GFP chemotherapy. Overall, survival in the adjuvant GFP group was significantly better than that in the non-adjuvant GFP group (3-year survival: 61.9% vs. 8.8%, p<0.001), as was relapse-free survival. CONCLUSION: Adjuvant GFP chemotherapy after hepatectomy may be a promising option for improving surgical outcomes in patients with advanced biliary carcinoma.

miR-223 and Stathmin-1 Expression in Non-tumor Liver Tissue of Patients with Hepatocellular Carcinoma.

AIM: Overexpression of stathmin (STMN1) has been reported for several tumor entities. STMN1 expression correlated with the detection of mutant p53, also suggesting loss-of-function-dependent mechanisms for its accumulation in hepatocellular carcinoma (HCC) cells. On the other hand, miR-223 has been identified as one of the most down-regulated miRNAs in HCC, and its expression was shown to be negatively correlated with STMN1 expression. The aim of this study was to investigate the clinical significance of STMN1 and miRNA-223 expression. PATIENTS AND METHODS: Fifty-six consecutive patients with HCC who underwent curative hepatectomy as initial treatment were enrolled. They were divided into two groups based on the STMN1 expression level: high (n=36) and low (n=20) gene-expression groups. We compared the clinicopathological factors between the groups with high and low expression in non-tumor tissues. Thirty out of 56 patients were also divided into groups with high (n=15) and low (n=15) miR-223 expression and compared the clinicopathological factors between the two groups. RESULTS: There were no significant differences in patient background between high and low STMN1 expression groups. The incidence of multicentric (MC) recurrence in the high-expression group was significantly higher than in the low-expression group and high STMN1 expression was shown to be an independent risk factor for MC recurrence. There were also no significant differences in patient background between high and low miR-223 expression groups; however, the disease-free survival rate in the group with low expression was significantly worse. Furthermore, MC-related miRNAs identified by miRNA microarray clearly clustered patients into MC recurrence and non-recurrence groups. CONCLUSION: Both gene and miRNA expression profiles in non-tumor liver tissues could predict the risk for MC recurrence. Such molecular information may be useful in enabling better decision making for patients with HCC.

Prevention against renal damage in rats with subtotal nephrectomy by sacubitril/valsartan (LCZ696), a dual-acting angiotensin receptor-neprilysin inhibitor.

Although patients with chronic kidney disease (CKD) are at increased risk for end-stage renal disease and cardiovascular events, adequate drug therapies for preventing the deterioration of these conditions are still not established. This study was undertaken to evaluate a preventive effect of an angiotensin receptor-neprilysin inhibitor sacubitril/valsartan (LCZ696), which is converted to sacubitril and valsartan in the body, against the progression of renal disease in rats with subtotal nephrectomy, an animal model of human CKD. Mean survival time after subtotal nephrectomy was about 100 days in Wistar rats with vehicle. LCZ696-(30 mg/kg) and valsartan-(15 mg/kg) prolonged the survival of these animals, and the effect of LCZ696 on survival was significantly greater than that of valsartan. Renoprotective effects of LCZ696 judged by serum creatinine and urinary protein excretions were larger than those of valsartan. Cardioprotective effects judged by cardiac left ventricular mass, fractional shortening, and fibrosis of LCZ696 and valsartan were not detected under the present condition. Thus, the renoprotective effect of LCZ696 was stronger than that of valsartan in rats with subtotal nephrectomy. This study provides the idea that, compared to valsartan, LCZ696 is more effective for the treatment of human CKD.

C-C Chemokine Receptor Type 2-Dependent Migration of Myeloid-Derived Suppressor Cells in Protection of Islet Transplants.

BACKGROUND: Islet transplantation is a promising therapeutic approach to restore the physical response to blood glucose in type 1 diabetes. Current chronic use of immunosuppressive reagents for preventing islet allograft rejection is associated with severe complications. In addition, many of the immunosuppressive drugs are diabetogenic. The induction of transplant tolerance to eliminate the dependency on immunosuppression is ideal, but remains challenging. METHODS: Addition of hepatic stellate cells allowed generation of myeloid-derived suppressor cells (MDSC) from precursors in mouse bone marrow. Migration of MDSC was examined in an islet allograft transplant model by tracking the systemic administered MDSC from CD45.1 congenic mice. RESULTS: The generated MDSC were expressed C-C chemokine receptor type 2 (CCR2), which was enhanced by exposure to interferon-γ. A single systemic administration of MDSC markedly prolonged survival of islet allografts without requirement of immunosuppression. Tracking the administered MDSC showed that they promptly migrated to the islet graft sites, at which point they exerted potent immune suppressive activity by inhibiting CD8 T cells, enhancing regulatory T cell activity. MDSC generated from CCR2 mice failed to be mobilized and lost tolerogenic activity in vivo, but sustained suppressive activity in vitro. CONCLUSIONS: MDSC migration was dependent on expression of CCR2, whereas CCR2 does not directly participate in immune suppression. Expression of CCR2 needs to be closely monitored for quality control purpose when MDSC are generated in vitro for immune therapy.

Complication of portal vein thrombosis after right hemihepatectomy in a patient lacking the portal vein bifurcation.

Absence of portal vein bifurcation is a rare anomaly. We report a patient with this anomaly who underwent right hemihepatectomy for treatment of hepatocellular carcinoma. Although the procedure was carefully performed with a preoperative three-dimensional simulation and intraoperative cholangiography, postoperative portal vein thrombosis occurred. J. Med. Invest. 63: 315-318, August, 2016.

Effects of telmisartan and olmesartan on insulin sensitivity and renal function in spontaneously hypertensive rats fed a high fat diet.

Although telmisartan, an angiotensin II receptor blocker (ARB), has an agonistic action for proliferator-activated receptor (PPAR)-γ in vitro, it remains to be determined whether telmisartan exerts such an action in vivo using a non-toxic dose (<5 mg/kg in rats). To address the issue, telmisartan (2 mg/kg) and olmesartan (2 mg/kg), another ARB without PPAR-γ agonistic action, were given to spontaneously hypertensive rats (SHR) fed a high fat diet (HFD). HFD decreased plasma adiponectin, and caused insulin resistance, hypertriglyceridemia and renal damage, which were improved by ARBs. Protective effects of telmisartan and olmesartan did not significantly differ. In addition, in vitro study showed that 1 µM of telmisartan did not elevate the mRNA expression of adipose protein 2, which is a PPAR-γ-stimulated adipogenic marker gene, in preadipocytes with 3% albumin. To obtain 1 µM of plasma concentration, oral dose of telmisartan was calculated to be 6 mg/kg, which indicates that PPAR-γ agonistic action is negligible with a non-toxic dose of telmisartan (<5 mg/kg) in rats. This study showed that 2 mg/kg of telmisartan and olmesartan ameliorated insulin resistance, hypertriglyceridemia and renal damage in SHR fed a HFD. As beneficial effects of telmisartan and olmesartan did not significantly differ, these were mediated through the PPAR-γ-independent actions.

Liver regeneration after splenectomy in patients with liver cirrhosis.

AIM: Splenectomy is a well-known procedure to improve thrombocytopenia and liver function in patients with liver cirrhosis (LC). However, the effect of splenectomy on liver regeneration remains unclear. The aim of this study is to investigate the effect of splenectomy on liver regeneration. METHODS: Twenty patients with LC who underwent splenectomy were included in this study. Liver and splenic volumes were measured by a 3-D simulation imaging system. Liver volume (LV) and clinicopathological data were compared before and 6 months after splenectomy. Thereafter, patients were divided into two groups: the elevated LV group and the reduced LV group. Patient characteristics were compared between the two groups. RESULTS: Postoperative LV was increased in 14 patients compared with the preoperative state. Thrombocytopenia, leukopenia, total bilirubin and prothrombin time were improved after splenectomy. In the elevated LV group, four patients exhibited improved Child-Pugh grades after splenectomy, whereas no patients demonstrated improvement in the reduced LV group. The elevated LV group exhibited high albumin level, good indocyanine green retention rate at 15 min and large splenic volume compared with the same measurements in the decreased group. Patients with larger spleen volumes and higher albumin values before splenectomy showed increased rates of LV after splenectomy. CONCLUSION: Splenectomy for patients with LC improved pancytopenia and liver function. Especially, in patients with large spleen and high albumin levels, considerable increases in LV and improved liver function were observed.

Epigallocatechin gallate hinders human hepatoma and colon cancer sphere formation.

BACKGROUND AND AIM: The long-term survival of patients with hepatocellular carcinoma remains unsatisfactory because of the presence of cancer stem cells (CSCs), which are responsible for tumor recurrence and chemoresistance after hepatectomy. Drugs that selectively target CSCs thus offer great promise for cancer treatment. Although the antitumor effects of epigallocatechin gallate (EGCG) have been reported in some cancer cells, its effects on CSCs remain poorly studied. In this study, we investigated the effects of EGCG on human hepatoma and colon CSCs. METHODS: HepG2 and HCT-116 cell lines were enriched by sphere formation, and their gene-expression profiles were analyzed by quantitative real-time polymerase chain reaction. EGCG-induced growth inhibition in the parental cells was determined by WST-8 assay, and protein expression was assessed by western blotting. Cell cycle profile and apoptosis analysis was performed using flow cytometer. RESULTS: Sphere-derived cells grown in serum-free, nonadherent cultures showed increased expression of stem cell markers, Nek2, and ATP-binding cassette transporter genes, compared with parental cells grown in conventional culture. EGCG induced growth inhibition in the parental cells in a dose-dependent manner. EGCG also inhibited self-renewal in hepatoma and colon CSCs, attenuated the expression of stem cell markers and ATP-binding cassette transporter genes, which are putative molecules associated with treatment resistance in CSCs, and decreased the transcription of Nek2 and p-Akt, resulting in the inhibition of Akt signaling. EGCG also altered cell cycle profile and apoptosis, which may in part play an important role in EGCG-induced cancer cell death. CONCLUSIONS: Overall, these results suggest that EGCG could be a useful chemopreventive agent for targeting hepatocellular carcinoma and colon CSCs, in combination with standard chemotherapies.