Hidehiko Hara

Does increased water intake prevent disease progression in autosomal dominant polycystic kidney disease

…with tolvaptan at present not being available for clinical care, other options that lower AVP activity should be considered. An alternative might be to lower AVP concentration by increasing water intake. In a rat model for polycystic kidney disease, a 3.5 fold increased water intake reduced urinary osmolality, renal expression of the AVP V2 receptor and reduced kidney weight compared to normal water intake…

Immunomagnetic quantification of circulating tumor cells in patients with urothelial cancer

Objectives:  To evaluate the relationship between circulating tumor cells (CTC) and clinical parameters in metastatic urothelial cancer (UC).

Local interferon-α gene therapy elicits systemic immunity in a syngeneic pancreatic cancer model in hamster

The interferon (IFN) protein is a cytokine with pleiotropic biological functions that include induction of apoptosis, inhibition of angiogenesis and immunomodulation. We previously examined the two antitumor mechanisms, taking advantage of the fact that IFN‐α did not show cross‐species activity in its in vivo effect. In a nude mouse subcutaneous xenograft model using human pancreatic cancer cells, the expression of human IFN‐α effectively induced cell death of human pancreatic cancer cells, whereas mouse IFN‐α augmented antitumor immunity by stimulation of natural killer cells. Here, we extended our investigation to a syngeneic pancreatic cancer model, so that the integrated antitumor activity of local IFN‐α gene therapy, including the antiproliferative, proapoptotic, antiangiogeneic and immunomodulatory effects, can be evaluated rigorously. When a recombinant hamster IFN‐α adenovirus was injected into syngeneic subcutaneous tumors of hamster pancreatic cancer (PGHAM‐1) cells in Syrian hamster, tumor growth was significantly suppressed due to cell death and T cell‐ and natural killer cell‐mediated antitumor immunity. Moreover, in this case, tumor regression was observed not only for the injected subcutaneous tumors but also for the untreated tumors both in the peritoneal cavity and at distant sites. No significant systemic toxicity was observed in the treated hamsters. Moreover, the subcutaneous rechallenge of PGHAM‐1 cells was rejected in three of four cured hamsters from the initial tumor challenge. This study further demonstrated that local IFN‐α gene therapy is a promising therapeutic strategy for pancreatic cancer, due to its multiple mechanisms of antitumor activity and its lack of significant toxicity. (Cancer Sci 2007; 98: 455–463))

Administration route-dependent induction of antitumor immunity by interferon-alpha gene transfer.

Type I interferon (IFN) protein is a cytokine with pleiotropic biological functions that include induction of apoptosis, inhibition of angiogenesis, and immunomodulation. We have demonstrated that intratumoral injection of an IFN‐α‐expressing adenovirus effectively induces cell death of cancer cells and elicits a systemic tumor‐specific immunity in several animal models. On the other hand, reports demonstrated that an elevation of IFN in the serum following an intramuscular delivery of a vector is able to activate antitumor immunity. In this study, we compared the intratumoral and systemic routes of IFN gene transfer with regard to the effect and safety of the treatment. Intratumoral injection of an IFN‐α adenovirus effectively activated tumor‐responsive lymphocytes and caused tumor suppression not only in the gene‐transduced tumors but also in distant tumors, which was more effective than the intravenous administration of the same vector. The expression of co‐stimulatory molecules on CD11c+ cells isolated from regional lymph nodes was enhanced by IFN gene transfer into the tumors. Systemic toxicity such as an elevation of hepatic enzymes was much lower in mice treated by intratumoral gene transfer than in those treated by systemic gene transfer. Our data suggest that the intratumoral route of the IFN vector is superior to intravenous administration, due to the effective induction of antitumor immunity and the lower toxicity. (Cancer Sci 2010)

Allogeneic MHC Gene Transfer Enhances an Effective Antitumor Immunity in the Early Period of Autologous Hematopoietic Stem Cell Transplantation

Purpose: In autologous hematopoietic stem cell transplantation (HSCT), lymphopenia-induced homeostatic proliferation of T cells is driven by the recognition of self-antigens, and there is an opportunity to skew the T-cell repertoire during the T-cell recovery by engaging tumor-associated antigens, leading to a break of tolerance against tumors. However, the homeostatic proliferation–driven antitumor responses seem to decline rapidly in association with tumor growth. We hypothesized that a tumor-specific immune response induced by an immune gene therapy could enhance and sustain homeostatic proliferation–induced antitumor immunity. Experimental Design: The antitumor effect of allogeneic MHC (alloMHC) gene transfer was examined at the early phase of the immune reconstitution after syngeneic HSCT. Results: Syngeneic HSCT showed significant tumor growth inhibition of syngeneic colon cancer cells within a period of 30 days; however, the tumor then resumed rapid growth and the survival of the mice was not prolonged. In contrast, when the alloMHC plasmid was intratumorally injected at the early phase after syngeneic HSCT, the established tumors were markedly regressed and the survival of recipient mice was prolonged without significant toxicities, whereas no survival advantage was recognized in recipient mice injected with a control plasmid. This tumor suppression was evident even in the other tumors that were not injected with the alloMHC plasmid. The antitumor response was characterized by the development of tumor-specific T cell– and natural killer cell–mediated cytotoxicities. Conclusion: The results suggest the efficacy and safety of integrating intratumoral alloMHC gene transfer with an autologous HSCT for the treatment of solid cancers.

Intratumoral interferon-α gene transfer enhances tumor immunity after allogeneic hematopoietic stem cell transplantation

One of the major challenges in the treatment of solid cancers by allogenic hematopoietic stem cell transfer (alloHSCT) is the specific enhancement of antitumor immunity. Interferon (IFN) is a cytokine with pleiotropic biological functions including an immunomoduration, and our preclinical studies have shown that an intratumoral IFN-α gene transfer induced strong local tumor control and systemic tumor-specific immunity. In the present study, we examined whether the IFN-α gene transfer could enhance recognition of tumor-associated antigens by donor T cells and augment the antitumor activity of alloHSCT. First, when a mouse IFN-α adenovirus vector (Ad-mIFN) was injected into subcutaneous xenografts of syngeneic renal and colon cancer cells, tumor growth was significantly suppressed in a dose-dependent manner. A significant tumor cell death and infiltration of immune cells was recognized in the Ad-mIFN-injected tumors, and the dendrtic cells isolated from the tumors showed a strong Th1-oriented response. The antitumor effect of Ad-mIFN was then examined in a murine model of minor histocompatibility antigen-mismatched alloHSCT. The intratumoral IFN-α gene transfer caused significant tumor suppression in the alloHSCT recipients, and this suppression was evident not only in the gene-transduced tumors but also in simultaneously inoculated distant tumors which did not receive the vector injection. A cytotoxicity assay showed specific tumor cell lysis by donor T cells responding to IFN-α. Graft-versus-host disease was not exacerbated serologically or clinically in the mice treated with IFN-α. This combination strategy deserves evaluation in future clinical trials for human solid cancers.

Kidney volume estimations with ellipsoid equations by magnetic resonance imaging in autosomal dominant polycystic kidney disease.

Background: Kidney volume (KV) becomes clinically relevant in autosomal dominant polycystic kidney disease (ADPKD) management. KV can be conveniently estimated (ceKV) using ellipsoid volume equations with three axes measurements; however, the accuracy and reliability are unknown. Methods: KVs of 347 kidneys in 177 consecutive ADPKD patients were determined with a volumetric method (standard-KV), and ceKV was calculated using six different ellipsoid equations with three axes measurements using magnetic resonance imaging. The inter- and intraobserver reliabilities were analyzed using intraclass correlation coefficients (ICCs). Ellipsoid-KVs were obtained by linear regression analysis between standard-KV and ceKVs, and six ellipsoid-KVs were validated with a bootstrap model. Results: The ICCs of intra- and interobserver reliabilities in standard-KV and axes measurements were highly reliable. All ceKVs underestimated standard-KV and % differences between ceKV and standard-KV were reduced by ellipsoid-KVs. Bootstrap analyses suggested that six ellipsoid-KVs reliably simulated standard-KV. Conclusion: Among six ellipsoid-KVs, ellipsoid-KV3 = 84 + 1.01 x π/24 × Length × (sum of two width measurements)2 relatively accurately simulated the standard-KV. Kidney volume estimation using ellipsoid equations is reliably applied to clinical management of ADPKD while recognizing wide scattering in the difference between estimated and volumetrically measured kidney volume.

Initial operative experience of single-port retroperitoneal laparoscopic nephrectomy

This paper reports our early experience with single‐port laparoscopic nephrectomy via the retroperitoneal approach. Since April 2010, 23 patients have undergone single‐port laparoscopic surgery for simple nephrectomy (n = 11 patients) and radical nephrectomy (n = 12) by an experienced laparoscopic surgeon. The mean operative time was 265.2 min and the mean estimated blood loss was 96.7 mL. The procedure was completed in all patients without conversion to standard laparoscopy or open surgery. No intraoperative or acute postoperative complications occurred. When the single‐port retroperitoneal laparoscopic nephrectomy group was retrospectively compared with the group that had undergone standard retroperitoneal laparoscopic nephrectomy, no significant difference was noted with respect to age, body mass index, operation time, time to eat, catheter removal or length of hospitalization (P > 0.05). A significant difference in favor of the single‐port retroperitoneal laparoscopic nephrectomy group was noted with respect to the estimated blood loss (P = 0.027) and the visual analog pain scale score at discharge (P = 0.016). Although our findings show that retroperitoneal single‐port laparoscopic nephrectomy is feasible with advanced techniques and optimal instrumentation, further study is required to determine the future extent of its clinical application.

Angiogenic, inflammatory and immunologic markers in predicting response to sunitinib in metastatic renal cell carcinoma

The objective of this prospective study was to identify baseline angiogenic and inflammatory markers in serum as well as the baseline levels of immune cells in whole blood to predict progression‐free survival in patients with metastatic renal cell carcinoma treated with sunitinib. Blood samples were collected at baseline in all 90 patients to analyze serum angiogenic and inflammatory markers together with peripheral blood immunological marker. The association between each marker and sunitinib efficacy was analyzed. Univariate and multivariate Cox proportional model analyses were used to assess the correlation between those markers with survival. Baseline levels of interleukin‐6, interleukin‐8, high sensitivity C‐reactive protein and myeloid‐derived suppressor cells were significantly higher in patients who progressed when compared with those with clinical benefit. Analysis by the Cox regression model showed that baseline interleukin‐8, high sensitivity C‐reactive protein and percentage of T helper type 1 cells were significantly associated with progression‐free survival in univariate analysis. Furthermore, in multivariate analysis, those three markers were independent indices to predict progression‐free survival. In conclusion, angiogenic (interleukin‐8), inflammatory (interleukin‐6, high sensitivity C‐reactive) and immunologic (myeloid‐derived suppressor cells, percentage of T helper type 1 cells) markers at baseline would predict the response to sunitinib therapy and/or disease progression in patients with metastatic renal cell carcinoma.

Epidermal Growth Factor Receptor Status in Circulating Tumor Cells as a Predictive Biomarker of Sensitivity in Castration-Resistant Prostate Cancer Patients Treated with Docetaxel Chemotherapy

Objective: We examined whether epidermal growth factor receptor (EGFR) expression in circulating tumor cells (CTCs) can be used to predict survival in a population of bone-metastatic castration-resistant prostate cancer (mCRPC) patients treated with docetaxel chemotherapy. Methods: All patients with mCRPC who had experienced treatment failure with androgen-deprivation therapy and had received docetaxel chemotherapy were eligible. CTCs and EGFR expression in CTCs were enumerated with the CellSearch System in whole blood. This system is a semi-automated system that detects and enriches epithelial cells from whole blood using an EpCAM antibody-based immunomagnetic capture. In addition, the EGFR-positive CTCs were assessed using CellSearch® Tumor Phenotyping Reagent EGFR. Results: The median CTC count at baseline before starting trial treatment was eight CTCs per 7.5 mL of blood (range 0–184). There were 37 patients (61.7%) who had ≥5 CTCs, with median overall survival of 11.5 months compared with 20.0 months for 23 patients (38.3%) with <5 CTCs (p < 0.001). A total of 15 patients (40.5%, 15/37) with five or more CTCs were subjected to automated immunofluorescence staining and cell sorting for EGFR protein. Patients with EGFR-positive CTCs had a shorter overall survival (OS) (5.5 months) than patients with EGFR-negative CTCs (20.0 months). CTCs, EGFR-positive CTCs, and alkaline phosphatase (ALP) were independent predictors of overall survival time (p = 0.002, p < 0.001, and p = 0.017, respectively). Conclusion: CTCs may be an independent predictor of OS in CRPC treated with docetaxel chemotherapy. The EGFR expression detected in CTCs was important for assessing the response to chemotherapy and predicting disease outcome.