Keijiro Kiyoshima

Usefulness of apparent diffusion coefficient map in diagnosing prostate carcinoma: Correlation with stepwise histopathology

To elucidate the performance of apparent diffusion coefficient (ADC) map in localizing prostate carcinoma (PC) using stepwise histopathology as a reference.

Foxo3a Suppression of Urothelial Cancer Invasiveness through Twist1, Y-Box–Binding Protein 1, and E-Cadherin Regulation

Purpose: Invasion and metastasis are key steps in the progression of urothelial cancer (UC) into a critical disease. Foxo3a is a member of the Foxo transcription factor family that modulates the expression of various genes. We aimed to elucidate the role of Foxo3a in UC invasion. Experimental Design: Foxo3a mRNA and protein expressions in UC samples were investigated by gene expression assays and immunohistochemistry, respectively. Foxo3a expression was compared with clinicopathologic characteristics and patient prognoses based on UC samples. Quantitative real-time polymerase chain reaction, Western blotting, and migration assays were also conducted in UC cells. Results: Foxo3a expression decreased in invasive UC; patients with low Foxo3a expression had poor disease-free survival, cancer-specific survival, and overall survival; Foxo3a knockdown in UC cells increased cellular motility. Foxo3a negatively regulated Twist1 and Y-box–binding protein 1 (YB-1), and positively regulated E-cadherin in KK47 and TCCsup cells that expressed Twist1, but not in T24 cells that did not express Twist1. Foxo3a-associated acetyltransferase p300 and Foxo3a acetylation status also affected UC motility. Conclusion: The results of this study indicate that Foxo3a regulates motility of UC through negative regulation of Twist1 and YB-1, and through positive regulation of E-cadherin. This suggests that Foxo3a could act as an independent prognostic factor in UC and could represent a promising molecular target for cancer therapeutics. Clin Cancer Res; 16(23); 5654–63. ©2010 AACR.

Oxidative stress and DNA hypermethylation status in renal cell carcinoma arising in patients on dialysis

Renal cell carcinoma (RCC) is more frequently observed in patients on dialysis than in patients with normal renal function. However, the mechanism underlying carcinogenesis in RCC patients on dialysis is still unclear. We hypothesized that oxidative stress affects patients on dialysis and generates new neoplasms, and therefore analysed the correlation between the influences of various markers of oxidative stress and carcinogenesis in those patients. We evaluated the immunohistochemical expression of oxidative stress markers, such as iNOS, 8‐OHdG, and COX‐2 in 42 cases on dialysis and 51 cases with normal renal function as a control. The methylation status of p16INK4a, p14ARF, VHL, and RASSF1A was analysed together with clinicopathological factors. Histologically, the papillary type was observed more frequently in dialysis RCC than in sporadic RCC. Immunohistochemically, overexpression of iNOS (p < 0.0001) and COX‐2 (p = 0.0002) was more frequently observed in dialysis RCC. Furthermore, the 8‐OHdG labelling index was significantly higher in dialysis RCC than in sporadic RCC. Hypermethylation of p16INK4a was more frequently found in dialysis RCC (p < 0.05). However, no significant correlations between oxidative stress markers and DNA hypermethylation status were observed. The overexpression of iNOS, COX‐2, and 8‐OHdG in dialysis RCC suggests that patients on dialysis are affected by oxidative stress and that this effect plays an important role in the genesis of dialysis RCC. Copyright

The feature of metabolic syndrome is a risk factor for biochemical recurrence after radical prostatectomy

To examine the association between the features of metabolic syndrome (MetS) (obesity, hypertension, diabetes mellitus, and dyslipidemia) and the risk of biochemical recurrence (BCR) after radical prostatectomy in patients with prostate cancer.

Multicentric papillary renal cell carcinoma associated with renal adenomatosis

A case of multicentric papillary renal cell carcinoma (RCC) associated with renal adenomatosis in the bilateral kidneys is reported. Bilateral multiple renal cysts in a 46‐year‐old man were pointed out incidentally by ultrasonography. Some of the left renal lesions were considered to be RCC, and left radical nephrectomy was performed accordingly. The left kidney was occupied by numerous solid nodules, which ranged from yellow to tan in color, and some of the large ones had foci of hemorrhage and necrosis. Microscopically, most of the tumors showed papillary RCC associated with renal adenoma, while others consisted only of adenomas. Ten months later, multiple lesions of the right kidney, which were initially considered to be multiple cysts, were found to have become enlarged and some of them were diagnosed as RCC. Thus, right radical nephrectomy was also performed, and these tumors showed the same features as the left renal tumors. The patients familial history was not remarkable. The kidneys revealed various histological features, ranging from dysplastic to adenoma or carcinoma, including transitional or overlapping features between them. The findings suggest an adenoma‐carcinoma sequence in papillary RCC. It is worth considering such entities.

Mechanism of Synergistic Antitumor Effect of Sorafenib and Interferon-α on Treatment of Renal Cell Carcinoma

PURPOSE The multikinase and tyrosine kinase inhibitor sorafenib has antitumor activity in patients with advanced renal cell carcinoma. Recent reports show the ability of sorafenib to synergize with interferon-α, leading to greater antitumor activity. We examined the underlying mechanism of sorafenib and interferon-α synergism for renal cell carcinoma treatment in vitro and in tumor bearing murine models. MATERIALS AND METHODS We used murine and human renal cell carcinoma cell lines for in vitro cell proliferation assay. ACHN (ATCC®) and RENCA tumors were subcutaneously transplanted into NCr-nu/nu and syngeneic BALB/c mice (Charles River Laboratories, Yokohama, Japan), respectively. Mice were treated with sorafenib and/or interferon-α, and tumor growth was monitored. Immunological assays were done in the RENCA model. RESULTS In the ACHN and RENCA cell lines combination index analysis clearly revealed the synergistic antiproliferative effects of interferon-α and sorafenib in vitro. In the ACHN NCr-nu/nu model we clearly noted the synergistic antitumor effects of interferon-α and sorafenib, indicating the synergistic direct effects of each drug on tumor growth. In the RENCA BALB/c model flow cytometry showed no change in the proportion of lymphocytes. However, while sorafenib alone did not induce natural killer or cytotoxic T-lymphocyte activity against RENCA in that model, interferon-α alone or combined with sorafenib induced natural killer and cytotoxic T-lymphocyte activity. CONCLUSIONS Our results show the synergistic activity of interferon-α and sorafenib. These findings provided the rationale for combination therapy with interferon-α and sorafenib in patients with advanced renal cell carcinoma.

Twist1 and Y-box-binding protein-1 are potential prognostic factors in bladder cancer

OBJECTIVE To investigate the expression and possible roles of Twist1 and Y-box-binding protein-1 (YB-1) in bladder cancer tissue. Twist1 belongs to the family of basic helix-loop-helix transcription factors. A functional link between Twist1 and YB-1 has recently been determined to play an important role in bladder cancer cell lines. MATERIALS AND METHODS Frozen samples from 75 patients with bladder cancer were analyzed by quantitative real-time polymerase chain reaction (PCR). Formalin-fixed and paraffin-embedded tissues from 53 patients with bladder cancer were examined by immunohistochemistry. RESULTS Twist1 transcript levels were positively correlated with YB-1 transcript levels (coefficient of correlation = 0.42, P<0.001), tumor grade (low grade vs. high grade; P<0.001), invasiveness (non-muscle-invasive bladder cancer vs. muscle invasive bladder cancer; P = 0.0018), and metastasis (meta- vs. meta+; P<0.001). YB-1 transcript level was also correlated with grade (P = 0.029) and invasiveness (P = 0.006). By immunohistochemistry, Twist1 expression was also correlated with YB-1 expression (P<0.001). Further, both Twist1 and YB-1 expression were positively correlated with invasiveness (P = 0.007 and P = 0.002, respectively). Patients with high Twist1 expression and high YB-1 expression had lower overall survival rates, compared with patients with low expression (log-rank test, P = 0.040 and P<0.001, respectively). CONCLUSIONS These results suggest a functional link between Twist1 and YB-1, and they indicate that Twist1 and YB-1 promote bladder cancer progression.

Renal Cancer Treatment with Low Levels of Mixed Chimerism Induced by Nonmyeloablative Regimen Using Cyclophosphamide in Mice

Recently, much attention has been paid to nonmyeloablative allogeneic stem cell transplantation for the treatment of metastatic renal cancer. Mature donor T cells cause graft-versus-host disease (GVHD) although they are also the main mediators of the beneficial graft-versus-tumor activity associated with this treatment. Hence, the segregation of the graft-versus-tumor activity from GVHD is an important challenge in managing the clinical course of treatment. We previously reported a series of studies regarding the allograft tolerance induced by allogeneic spleen cells (with bone marrow cells) and cyclophosphamide in mice. Here, we show a modified cyclophosphamide-induced tolerance system for the treatment of murine renal cell carcinoma, RENCA, by shifting the equal balance between graft-versus-host and host-versus-graft reactions toward graft-versus-host reaction with donor lymphocyte infusion. Our results clearly show the antitumor activity against RENCA with only low levels of mixed chimerism in the periphery and the in vivo and in vitro acquired immunity against RENCA even when mixed chimerism is almost undetectable. Because the withdrawal of mixed chimerism reduces the risk of GVHD, the antitumor activity is thus sequentially segregated from the initial GVHD in our model. We believe that this is the first unique model system of nonmyeloablative allogeneic hemopoietic cell transplantation to ever be reported for the treatment of renal cancer.

A male case of primary retroperitoneal mucinous cystadenoma: a diagnostic dilemma

We report a male case of primary retroperitoneal mucinous cystadenoma (PRMC) that was at initially misdiagnosed as a complicated renal cyst. On ultrasonography, a71-year-old man was found to have an abdominal mass suspicious for right renal cyst. The initial computed tomography scan showed an unenhanced, low-density mass that deformed the edge of the right kidney into a beak shape. Four years later, the mass had increased in size. Magnetic resonance imaging revealed a cystic lesion. Its intracystic content showed relatively high intensity on a T1-weighted image, and the coronal gadolinium-enhanced T1-weighted image with fat suppression clearly showed a multilocular cystic mass without enhancing mural nodules. The final diagnosis of PRMC was obtained pathologically after surgery. Because PRMC has malignant potential, this rare entity should be considered when a retroperitoneal cystic tumor is evaluated, even in a male patient.

Posttransplant administration of cyclophosphamide and donor lymphocyte infusion induces potent antitumor immunity to solid tumor

Purpose: Nonmyeloablative allogeneic stem cell transplantation (SCT) has been increasingly used for the treatment of hematologic and solid malignancies, and mature donor T cells are considered to be the main effectors of the graft-versus-tumor (GVT) activity. However, the association between degree of donor chimerism and intensity of GVT effects has not been fully elucidated. We recently proposed a unique nonmyeloablative cell therapy using posttransplant cyclophosphamide and donor lymphocyte infusion, by which a significant antitumor effect against murine renal cell carcinoma, RENCA, was induced, although the level of mixed chimerism was relatively low. In this study, we attempted to clarify a role of chimerism for in vivo antitumor effects on GVT effects in radiation-associated nonmyeloablative SCT. Experimental Design: We assessed antitumor effects on RENCA tumors and the degree of donor chimerism after several doses of irradiation followed by allogeneic SCT and compared the results with those of cyclophosphamide-based cell therapy. Results: Allogeneic SCT following sublethal irradiation (6 Gy) induced almost complete donor chimerism, whereas cyclophosphamide-based cell therapy produced low levels of donor chimerism. Nonetheless, GVT activity was much more potent in cyclophosphamide-based cell therapy than irradiation-conditioned SCT. Furthermore, cyclophosphamide-conditioned SCT induced more potent immune reconstitution with less severe graft-versus-host disease than irradiation-conditioned SCT. Conclusions: Our results indicate that a high level of chimerism is not essential for the in vivo antitumor effect of nonmyeloablative allogeneic cell therapy against solid tumor and that the recovery of peripheral lymphocytes after the initial immunosuppression might be a critical event for the elicitation of in vivo antitumor effects of that treatment modality.