Hepatic differentiation of human bone marrow-derived UE7T-13 cells: Effects of cytokines and CCN family gene expression

Aim: Bone marrow-derived mesenchymal stem cells (MSC) are expected to be an excellent source of cells for transplantation. We aimed to study the culture conditions and involved genes to differentiate MSC into hepatocytes. Methods: The culture conditions to induce the efficient differentiation of human bone marrow-derived UE7T-13 cells were examined using cytokines, hormones, 5-azacytidine and type IV collagen. Results: We found that combination of acidic fibroblast growth factor (aFGF), basic fibroblast growth factor (bFGF) and hepatocyte growth factor (HGF) with type IV collagen coating induced hepatic differentiation of UE7T-13 cells at over 30% frequency, where expression of albumin mRNA was increased over 20-fold. The differentiated cells had functions of albumin production, glycogen synthesis and urea secretion as well as expressing hepatocyte-specific genes. In addition, these cellshave binuclear and cuboidal morphology, which is a characteristic feature of hepatocytes. During hepatic differentiation, UE7T-13 cells showed depressed expression of WISP1 and WISP2 genes, members of the CCN family. Conversely, knockdown of WISP1 or WISP2 gene by siRNA stimulated hepatic differentiation. The effect of aFGF/bFGF/HGF/type IV collagen coating and WISP1-siRNA on hepatic differentiation was additive. Conclusion: The present study suggests that aFGF/bFGF/HGF/type IV collagen coating is the efficient condition for hepatic differentiation of UE7T-13 cells, and that WISP1 and WISP2 play an important role in hepatic transdifferentiation of these cells.     

Progress in stem cell biology in regenerative medicine for liver disease

Regenerative medicine using stem cells has attracted much attention, since stem cells are responsible for highly proliferative activity and multipotential ability of differentiation. Induced pluripotent stem cells and embryonic stem cells or the adult stem cells such as bone marrow-derived stem cells and adipose tissue-derived stem cells have been expected as a cell source of regenerative medicine. Since differentiating methods of human stem cells into the defined lineage of cells remains to be developed, we focus on the differentiating strategies of pluripotent stem cells and mesenchymal stem cells into liver lineage, especially on cytokine function and gene expression during hepatic differentiation. The survey of previously published papers discloses that the protocols that mimic the liver developmental process seem to be effective in obtaining functional hepatocytes. However, in order to develop hepatic regenerative medicine that is useful in a clinical setting, more effective and potent strategies that obtain mature hepatocytes are required.     

Decrease of creatinine clearance rate with aging in patients with head and neck cancer in Japan

Background We aimed to clarify the reason for the lower dosage of cis-platinum (CDDP) in patients with head and neck cancer in Japan compared with that in other countries, by evaluating renal function. Methods We studied 375 patients with head and neck cancer who had been hospitalized from January 1998 to October 2005, to evaluate and treat the disease. The creatinine clearance rate (Ccr) was calculated at least three times before beginning the treatments, and the average Ccr was estimated to evaluate the renal function. Results The Ccr decreased with aging, and the percentages of patients with Ccr lower than 65 ml/min per 1.73 m² were 27.1% of patients in their fifties, 36.8% in their sixties, 62.3% in their seventies, and 87.5% in their eighties. There was no correlation between renal function and the Japanese lifestyle (i.e., diet. water consumption). Conclusion The renal function of Japanese decreases rapidly with aging, whereas that of Americans is maintained for longer periods. The poor renal function of Japanese is one of the causes of the need to reduce the dosage of or avoid the administration of CDDP in cancer patients.     

Protein levels of p21, p27, cyclin E and Bax predict sensitivity to cisplatin and paclitaxel in head and neck squamous cell carcinomas

Regression of tumor mass by chemotherapy is caused by growth suppression and/or apoptosis of tumor cells. Therefore, expression levels of cell cycle molecules and apoptosis should be predictive markers for the efficacy of a drug. In the present study, the relationship between expression of molecules in the cell cycle and apoptosis and chemosensitivity was investigated in head and neck squamous cell carcinoma cell lines. Expression of p53, p21, p27, cyclin D1, cyclin E, and Bax in 17 such cell lines were analyzed by Western blot analysis. The concentrations of four chemotherapeutic agents (cisplatin, 5-FU, vincristine, and paclitaxel) resulting in 50% cell growth inhibition were calculated as IC50 values for each cell line. Cell cycle analysis was performed using a FACScan flow cytometer. Cells with strong expression of p21, p27, or Bax showed significantly higher sensitivity to cisplatin, and cells with strong expression of Bax or weak expression of cyclin E showed significantly higher sensitivity to paclitaxel. Cisplatin most effectively killed cells expressing both p21 and p27 or either at G1 phase. Though the assessments of p21, p27, Bax, and cyclin E expression in tumor tissues have been reported to be useful as prognostic factors in head and neck squamous cell carcinoma, these correlations might not only describe the malignant biological behavior of the tumor, but also the response to chemotherapy. Furthermore, p21/p27 expression might be a useful guide for the choice of chemotherapeutic agents.     

Synergistic effects of (-)-epigallocatechin gallate with sulindac against colon carcinogenesis of rats treated with azoxymethane.

(-)-Epigallocatechin gallate (EGCG), a major constituent of green tea, has been shown to exhibit anti-cancer activity. Sulindac is also well known as a cancer-preventive agent against colon cancer, but its usage is restricted because of its adverse effects, as exemplified by gastrointestinal bleeding. In the present study, we examined whether a combination of EGCG and sulindac shows synergistic effects for cancer-preventive activity for rat colon carcinogenesis induced by azoxymethane (AOM); we examined the number of aberrant crypt foci (ACF) representing preneoplastic lesions, the argyrophilic nucleolar organizer region (AgNOR) as an indicator of cell proliferation, and the incidence of apoptosis. The AOM treatment induced an average of 46.2+/-4.9 ACF/colon, and sulindac and EGCG significantly reduced the incidence of ACF/colon to 21.4+/-3.4 and 19.5+/-5.8, respectively (P<0.01). The co-treatment with EGCG and sulindac resulted in significantly reduced ACF formation (10.0+/-3.2; P<0.01). The results of the AgNOR analysis indicated that the treatment with EGCG and/or sulindac suppressed AOM-induced cell proliferation. The present results also revealed that the combination of EGCG and sulindac synergistically enhanced apoptosis significantly (P<0.01). Thus, our findings suggest that EGCG with sulindac synergistically suppresses ACF formation by enhancing apoptosis and, therefore, that EGCG is a suitable candidate for use in combination with cancer-preventive agents, such as sulindac, to reduce their adverse effects.     

Antitumor effects of IDN5109 on head and neck squamous cell carcinoma

Taxanes, a new class of antitumor drugs, are effective against a large number of human tumors, although there are problems with drug resistance. The novel taxane, IDN5109, is characterized by its high tolerability, antitumor efficacy, ability to overcome multidrug resistance, and oral bioavailabilty. We investigated the cellular response of IDN5109 to head and neck squamous cell carcinoma (HNSCC), and compared the antitumor activity of IDN5109 with that of paclitaxel. This is the first demonstration of antitumor effects of IDN5109 on HNSCC. In in vitro experiments, IDN5109 showed antiproliferative effects against HNSCC cell lines. After treatment with IDN5109, Bcl-2 and Bcl-XL were down-regulated, Bax was up-regulated, and caspase-3 was activated. After treatment with IDN5109, concentrations of both VEGF and IL-8 in the culture supernatant of HNSCC cells decreased. In in vivo experiments, the oral administration of IDN5109 showed antitumor effects against HNSCC tumor xenografts. Immunohistochemistry showed that IDN5109 inhibited tumor angiogenesis and induced apoptosis in HNSCC cells, producing a decreased blood vessel density and increased apoptosis index. On the basis of these results, IDN5109 is useful as a chemotherapeutic agent against HNSCC.