Overexpression of SerpinB9 in non-seminomatous germ cell tumors

Serpinb9 is an inhibitor of granzyme B and is potentially involved in the immune escape of tumor cells. In the present study, bioinformatics analysis using open databases suggested that SerpinB9 is overexpressed in testicular embryonal carcinoma. Immunohistological analysis was performed on 28 cases of testicular germ cell tumors to investigate the relationship between SerpinB9 expression in testicular germ cell tumors and the tumor immune environment. SerpinB9 was significantly upregulated in the non-seminoma group and inversely correlated with the number of tumor-infiltrating CD8-positive cells. In addition, yolk sac tumors were characterized by the loss of human leukocyte antigen-class I expression. These findings suggest that SerpinB9 contributes to the immune escape of testicular germ cell tumors. Targeting therapy for SerpinB9 might therefore be useful in immunotherapy for testicular germ cell tumors resistant to immune checkpoint inhibitors.

Dysfunction of sinus macrophages in tumor-bearing host induces resistance to immunotherapy

Sinus macrophages in draining lymph nodes (DLNs) are involved in anti-tumor immune reactions. CD169 (Sialoadhesin, Siglec-1) is expressed on sinus macrophages and is considered a surrogate marker for the immunostimulatory phenotype of macrophages. In this study, the significance of sinus macrophages in immunotherapy was evaluated using mouse models. Treatment with anti-programmed death-ligand 1 (PD-L1) antibody suppressed the subcutaneous tumor growth of MC38 and E0771 cells but was not effective against MB49 and LLC tumors. Decreased cytotoxic T-lymphocyte (CTL) infiltration in tumor tissues and CD169 expression in sinus macrophages were observed in MB49 and LLC cells compared to corresponding parameters in MC38 and E0771 cells. The anti-tumor effects of the anti-PD-L1 antibody on MC38 and E0771 cells were abolished when sinus macrophages in DLNs were depleted, suggesting that sinus macrophages are involved in the therapeutic effect of the anti-PD-L1 antibody. Naringin activated sinus macrophages. Naringin inhibited tumor growth in MB49- and LLC-bearing mice but did not affect that in MC38- and E0771-bearing mice. The infiltration of CTLs in tumor tissues and their activation were increased by naringin, and this effect was impaired when sinus macrophages were depleted. Combination therapy with naringin and anti-PD-L1 antibody suppressed MB49 tumor growth. In conclusion, CD169-positive sinus macrophages in DLNs are critical for anti-tumor immune responses, and naringin suppresses tumor growth by activating CD169-positive sinus macrophages and anti-tumor CTL responses. The activation status of sinus macrophages has been suggested to differ among tumor models, and this should be investigated in future studies.

Predictive value of CXCL10 for the occurrence of immune-related adverse events in patient with renal cell carcinoma

Immune checkpoint inhibitors (ICIs) have recently improved the prognosis of various cancers. By contrast, some immune-related adverse events (irAEs) caused by ICIs are fatal and have become problematic. The pathogenesis of irAEs remains unknown and must be elucidated to establish biomarkers. This study investigated plasma cytokine, chemokine, and anti-CD74 autoantibody levels in patients with renal cell carcinoma (RCC) and analyzed their association with irAEs. In a discovery cohort of 13 patients, plasma levels of chemokine (C-X-C motif) ligand (CXCL) 1, IL-17A, IL-1β, IL-6, IL-8, CXCL10, MCP-1, and TNFα were measured at baseline and post-dose 1. Only CXCL10, at post-dose 1 but not at baseline, was significantly associated with grade 2 or higher irAEs (P = 0.0413). Plasma CXCL10 levels were then measured at baseline and post-dose 1 in an extended cohort of 43 patients with RCC who received ICI-based treatment. Higher plasma CXCL10 levels both at baseline and post-dose1 were significantly associated with the occurrence of grade 2 or higher irAEs (P = 0.0246 and 0.0137, respectively). Plasma CXCL13 levels, which we measured in a previous study, were significantly higher in patients with grade 2 or higher irAEs at baseline but not at post-dose 1 (P = 0.0037 and 0.052, respectively). No significant association between plasma anti-CD74 autoantibody level and both irAE pneumonitis and any grade 2 or higher irAE was observed. In conclusion, plasma CXCL10 is significantly associated with the occurrence of irAEs in patients with RCC treated with ICIs. CXCL10 is a potential predictive and on-treatment biomarker for irAEs.

A Case Report of Aggressive Fumarate Hydrase-deficient Renal Cell Carcinoma With Loss of HLA Antigens

BACKGROUND

Fumarate hydratase (FH)-deficient renal cell carcinoma (RCC) is a rare RCC subtype, and FH-deficient RCC may be misdiagnosed as another type of RCC, such as type 2 papillary RCC or collecting duct carcinoma. FH and 2-succinocysteine (2SC) are useful diagnostic markers for FH-deficient RCC and can be measured using immunohistochemistry (IHC).

CASE REPORT

A 30-year-old female with 3-month history of fatigue and left-flank mass was diagnosed with a 20×13×10 cm left-side renal mass with massive inferior vena cava (IVC) tumor thrombus that extended into the right atrium. She underwent nephrectomy and IVC thrombectomy, and a pathological diagnosis of type 2 papillary RCC was made. Four months after the surgery, computed tomography scan showed multiple liver metastases not observed immediately after surgery. Systemic treatment with sorafenib was initiated; however, she did not respond and died 3 months after treatment. Subsequent re-review of hematoxylin and eosin-stained sections indicated morphologic characteristics consistent with FH-deficient RCC, and IHC staining was negative for FH but positive for 2SC, indicating a diagnosis of FH-deficient RCC. Further immunological analyses revealed the loss of HLA-class I, b2 microglobulin, and HLA-DR antigens in cancer cells. In addition, a few CD8-positive cytotoxic T cells and CD163-positive tumor-associated macrophages were noted.

CONCLUSION

An immunosuppressive tumor microenvironment that facilitates cancer immune evasion might be associated with the rapid progression and poor prognosis in our patient. Further investigation of the tumor immune microenvironment in patients with FH-deficient RCC is warranted.

Abstract 4326: Predictive value of CXCL10 for the occurrence of immune related adverse events in patient with renal cell carcinoma

Background: Immune checkpoint inhibitors (ICIs) have recently improved the prognosis of various cancers. In contrast, some immune-related adverse events (irAEs) caused by ICIs are fatal and have become problematic. The pathogenesis of irAEs remains unknown and must be elucidated to establish biomarkers.

Materials and Methods: Plasma samples were collected prospectively from patients with advanced and metastatic renal cell carcinoma (RCC) prior to initiation of ICI treatment (baseline) and 2 or 3 weeks after the first cycle of ICI treatment (post-dose 1). Plasma cytokines and chemokines (GRO [CXCL1], IL-17A, IL-1β, IL-6, IL-8, IP-10 [CXCL10], MCP-1 [CCL2], TNFα) were measured by Luminex system, and plasma level of CXCL13 and anti-CD74 autoantibody levels were measured by ELISA. Their association with irAEs was analyzed.

Results: In a discovery cohort of 13 patients, plasma levels of CXCL1, IL-17A, IL-1β, IL-6, IL-8, CXCL10, MCP-1, and TNFα were measured at baseline and post-dose 1. Only CXCL10, at post-dose 1 but not at baseline, was significantly associated with grade 2 or higher irAEs (p=0.0413). Plasma CXCL10 levels were then measured at baseline and post-dose 1 in a validation cohort of 43 RCC patients who received ICI-based treatment. Higher plasma CXCL10 levels both at baseline and post-dose1 were significantly associated with the occurrence of grade 2 or higher irAEs (p=0.0246 and 0.0137, respectively). We evaluated the relationship between plasma levels of CXCL10 and CXCL13, which we measured in a previous study, and the incidence of irAEs. At baseline, the plasma CXCL13 level was positively associated with the CXCL10 level (p=0.0007), but no significant association was observed post-dose 1 (p=0.2678). Plasma CXCL13 levels were significantly higher in patients with grade 2 or higher irAEs at baseline but not at post-dose 1 (p=0.0037 and 0.052, respectively). No significant association between plasma anti-CD74 autoantibody level and both irAE pneumonitis and any grade 2 or higher irAE was observed.

Conclusion: Plasma CXCL10 is significantly associated with the occurrence of irAEs in patients with RCC treated with ICIs. CXCL10 is a potential predictive and on-treatment biomarker for irAEs.

Citation Format: Yuji Miura, Takanobu Motoshima, Toshiki Anami, Hiromu Yano, Remi Mito, Shinji Urakami, Keiichi Kinowaki, Hirotake Tsukamoto, Ryoma Kurahashi, Yoji Murakami, Junji Yatsuda, Yukio Fujiwara, Tomomi Kamba, Yoshihiro Komohara. Predictive value of CXCL10 for the occurrence of immune related adverse events in patient with renal cell carcinoma. [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 4326.

Sicca syndrome during ipilimumab and nivolumab therapy for metastatic renal cell carcinoma

Introduction

Dry mouth is the main symptom of sicca syndrome, which rarely occurs as an immune-related adverse event. Here we report a case of sicca syndrome caused by immune checkpoint inhibitor treatment.

Case presentation

A 70-year-old man was diagnosed with left renal cell carcinoma after radical left nephrectomy. Nine years later, computed tomography revealed a metastatic nodule in the upper left lung lobe. Subsequently, ipilimumab and nivolumab were administered for recurrent disease. After 13 weeks of treatment, xerostomia and dysgeusia were noted. Salivary gland biopsy revealed lymphocyte and plasma cell infiltration in the salivary glands. Sicca syndrome was diagnosed and pilocarpine hydrochloride was prescribed without corticosteroids, with continuation of immune checkpoint inhibitor therapy. The symptoms alleviated after 36 weeks of treatment, with shrinkage of the metastatic lesions.

Conclusion

We experienced sicca syndrome caused by immune checkpoint inhibitors. Sicca syndrome improved without steroids and the immunotherapy could be continued.

Efficacy of avelumab plus axitinib for advanced renal cell carcinoma as late-line therapy: A case report

A 46-year-old man developed a right renal tumor with multiple lung and hilar lymph node metastases. Laparoscopic radical nephrectomy was performed, and clear cell renal cell carcinoma was diagnosed 6 years earlier. Despite the use of available systemic therapeutic agents, atelectasis in the right upper lobe due to a pulmonary hilar mass and brain metastases reduced his performance, and he was becoming terminally ill. After administration of avelumab plus axitinib as 9th-line therapy, significant shrinkage of the metastases and improvement in performance status were observed. This case indicates the possibility of using avelumab plus axitinib as late-line therapy.

Clear cell carcinoma of the seminal vesicle in a young adult

Introduction

Most seminal vesicle malignancies are secondary to prostate or bladder cancer. Herein, we report a case of primary clear cell carcinoma of the seminal vesicle.

Case presentation

A 27‐year‐old man was referred to our department for hematospermia and macroscopic hematuria. A digital rectal examination showed a soft elastic prostatic mass. Cystoscopy showed no bladder abnormalities, and tumor marker tests were unremarkable. Contrast‐enhanced computed tomography and magnetic resonance imaging revealed a cystic tumor containing an enhanced nodule near the prostate and seminal vesicle. The tumor was removed en bloc with the prostate and seminal vesicle through a laparoscopic radical prostatectomy. A histopathologic examination confirmed the diagnosis, with the tumor likely arising from a remnant Müllerian epithelium. A 1‐year follow‐up revealed local tumor recurrence, prompting laparoscopy.

Conclusion

A standard therapy for primary seminal vesicle carcinoma has not been established. Further studies are necessary to determine the optimal treatment strategy.

Subcapsular renal hematoma after ureterorenoscopy

Introduction

Subcapsular renal hematoma after ureterorenoscopy using a holmium yttrium‐aluminum‐garnet laser is a rare complication. We experienced a case of subcapsular hematoma after ureterorenoscopy.

Case presentation

The patient was a 56‐year‐old man with a history of hypertension and coronary vasospastic angina, and he was taking antiplatelet drugs. He had the middle and lower calyx stones measured 36 mm in diameter of the right kidney. We performed ureterorenoscopy, which was completed about 2 h without intraoperative complications. We could not remove the stone completely. After the surgery, the patient developed a fever and complained of right back pain. Computed tomography showed several residual stones formed a stone street, obstructing the stent and resulting in grade 3 hydronephrosis. Furthermore, the right subcapsular renal hematoma infection had detected. Percutaneous hematoma drainage and percutaneous nephrostomy were performed.

Conclusion

Subcapsular renal hematoma after ureterorenoscopy is an uncommon complication but should be kept in mind.

Targeting chemoresistance in Xp11.2 translocation renal cell carcinoma using a novel polyamide-chlorambucil conjugate

Renal cell carcinoma with Xp11.2 translocation involving the TFE3 gene (TFE3‐RCC) is a recently identified subset of RCC with unique morphology and clinical presentation. The chimeric PRCC‐TFE3 protein produced by Xp11.2 translocation has been shown to transcriptionally activate its downstream target genes that play important roles in carcinogenesis and tumor development of TFE3‐RCC. However, the underlying molecular mechanisms remain poorly understood. Here we show that in TFE3‐RCC cells, PRCC‐TFE3 controls heme oxygenase 1 (HMOX1) expression to confer chemoresistance. Inhibition of HMOX1 sensitized the PRCC‐TFE3 expressing cells to genotoxic reagents. We screened for a novel chlorambucil–polyamide conjugate (Chb) to target PRCC‐TFE3‐dependent transcription, and identified Chb16 as a PRCC‐TFE3‐dependent transcriptional inhibitor of HMOX1 expression. Treatment of the patient‐derived cancer cells with Chb16 exhibited senescence and growth arrest, and increased sensitivity of the TFE3‐RCC cells to the genotoxic reagent etoposide. Thus, our data showed that the TFE3‐RCC cells acquired chemoresistance through HMOX1 expression and that inhibition of HMOX1 by Chb16 may be an effective therapeutic strategy for TFE3‐RCC.

STAT3 polymorphism associates with mTOR inhibitor-induced interstitial lung disease in patients with renal cell carcinoma

We evaluated the association of signal transducer and activator of transcription 3 (STAT3) polymorphisms with the incidence of mammalian target of rapamycin (mTOR) inhibitor-induced interstitial lung disease (ILD) in patients with renal cell carcinoma (RCC). We also used lung-derived cell lines to investigate the mechanisms of this association. Japanese patients with metastatic RCC who were treated with mTOR inhibitors were genotyped for the STAT3 polymorphism, rs4796793 (−1697C/G). We evaluated the association of the STAT3 genotype with the incidence of ILD and therapeutic outcome. In the 57 patients included in the primary analysis, the ILD rate within 140 days was significantly higher in patients with the GG genotype compared with those with other genotypes (77.8% vs. 23.1%, odds ratio = 11.67, 95% confidential interval = 3.06–44.46). There were no significant differences in progression-free survival or time-to-treatment failure between the patients with the GG genotype and those with other genotypes. An in vitro study demonstrated that some lung-derived cell lines carrying the GG genotype exhibited an increase in the expression of mesenchymal markers, such as fibronectin, N-cadherin, and vimentin, and decreases in E-cadherin, which is an epithelial marker associated with exposure to everolimus, although STAT3 expression and activity were not related to the genotype. In conclusion, the GG genotype of the STAT3 rs4796793 polymorphism increases the risk of mTOR inhibitor-induced ILD, supporting its use as a predictive marker for RCC.

HLA-DR and CD74 Expression and the Immune Microenvironment in Renal Cell Carcinoma

BACKGROUND/AIM

Expression of human leukocyte antigen (HLA) class I and II and CD74, which functions as a chaperone of MHC class II, play essential roles in T-cell recognition. The aim of this study was to elucidate the association between the HLAs and CD74, and their correlation with the infiltrated immune cells in renal cell carcinoma (RCC).

MATERIALS AND METHODS

We retrospectively investigated the expression of HLA-A/B/C, HLA-DR, and CD74 in 38 patients with advanced RCC (T3/T4), and evaluated their correlations with CD4 and CD8-positive T-cell infiltration using immunohistochemistry.

RESULTS

The expression of HLA-A/B/C, HLA-DR, and CD74 on cancer cells was observed in 37, 20, and 31 patients, respectively. The density of CD8- and CD4-positive T cells showed a positive correlation with HLA-DR expression. The density of CD4-positive lymphocytes was significantly associated with CD74 expression.

CONCLUSION

The expression of HLA-DR, rather than CD74, on cancer cells was potentially associated with the anti-cancer immune microenvironment.

High T-cell infiltration in tumor tissue and younger age predict the response to pembrolizumab in recurrent urothelial cancer

Targeting the programmed cell death-1 signaling pathway has been approved for the anti-cancer therapy in several cancers including urothelial cancer. To determine predictive factors of the responsiveness to pembrolizumab in urothelial cancer patients, a retrospective study that used clinical information and paraffin-embedded samples obtained from patients diagnosed with urothelial cancer between 2015 and 2020 were performed. Seventeen patients who underwent total cystectomy or nephroureterectomy of the primary lesion and were treated with pembrolizumab for chemo-resistant disease were enrolled, and immunohistochemical analysis was performed. A key difference in the characteristics between the non-responder group and the responder group was the age of the patients (74 vs. 63 years, p = 0.0194). Although there was no statistically significant difference, the histological subtype with sarcomatoid and micropapillary components was only seen in the non-responder group, and squamous differentiation and lymph node metastasis were only seen in cases with a complete response. In the results of immunohistochemistry, the density of CD8-positive T-cells and Tregs was significantly increased in the responder group than in the non-responder group. In conclusion, younger age and a high number of tumor-infiltrating lymphocytes were predictive factors of a good response to immune checkpoint inhibitors, although further studies with more enrolled patients are necessary.

Remarkable antitumor effect of nivolumab in a patient with metastatic renal cell carcinoma previously treated with a peptide-based vaccine

INTRODUCTION

The safety and efficacy of combination therapy comprising immune checkpoint inhibitors and cancer-specific peptide vaccines have not yet been established.

CASE PRESENTATION

A 71-year-old female metastatic renal cell carcinoma patient with multiple lung and pleural metastases. She had been treated with interferon alpha, sunitinib, axitinib, and pazopanib sequentially, but no clinical efficacy was observed. She participated in a clinical trial using cancer-specific peptide vaccine therapy. Initially no antitumor effect was observed, and vaccine therapy was ceased after two courses. But 3 months after the start of nivolumab, remarkable tumor shrinkage was observed at all metastatic sites, which resulted in almost complete response at 6 months. At 10 months, nivolumab was stopped due to cellulitis at the peptide vaccine inoculation site. Intriguingly, even after nivolumab discontinuation, complete response was maintained for more than 1 year.

CONCLUSION

We experienced a remarkable antitumor effect by nivolumab in a patient who was previously treated with vaccine therapy.

TFE3 Xp11.2 Translocation Renal Cell Carcinoma Mouse Model Reveals Novel Therapeutic Targets and Identifies GPNMB as a Diagnostic Marker for Human Disease

Renal cell carcinoma (RCC) associated with Xp11.2 translocation (TFE3-RCC) has been recently defined as a distinct subset of RCC classified by characteristic morphology and clinical presentation. The Xp11 translocations involve the TFE3 transcription factor and produce chimeric TFE3 proteins retaining the basic helix-loop-helix leucine zipper structure for dimerization and DNA binding suggesting that chimeric TFE3 proteins function as oncogenic transcription factors. Diagnostic biomarkers and effective forms of therapy for advanced cases of TFE3-RCC are as yet unavailable. To facilitate the development of molecular based diagnostic tools and targeted therapies for this aggressive kidney cancer, we generated a translocation RCC mouse model, in which the PRCC-TFE3 transgene is expressed specifically in kidneys leading to the development of RCC with characteristic histology. Expression of the receptor tyrosine kinase Ret was elevated in the kidneys of the TFE3-RCC mice, and treatment with RET inhibitor, vandetanib, significantly suppressed RCC growth. Moreover, we found that Gpnmb (Glycoprotein nonmetastatic B) expression was notably elevated in the TFE3-RCC mouse kidneys as seen in human TFE3-RCC tumors, and confirmed that GPNMB is the direct transcriptional target of TFE3 fusions. While GPNMB IHC staining was positive in 9/9 cases of TFE3-RCC, Cathepsin K, a conventional marker for TFE3-RCC, was positive in only 67% of cases. These data support RET as a potential target and GPNMB as a diagnostic marker for TFE3-RCC. The TFE3-RCC mouse provides a preclinical in vivo model for the development of new biomarkers and targeted therapeutics for patients affected with this aggressive form of RCC. IMPLICATIONS: Key findings from studies with this preclinical mouse model of TFE3-RCC underscore the potential for RET as a therapeutic target for treatment of patients with TFE3-RCC, and suggest that GPNMB may serve as diagnostic biomarker for TFE3 fusion RCC.

CD169-positive sinus macrophages in the lymph nodes determine bladder cancer prognosis

CD169⁺ macrophages are suggested to play a pivotal role in establishing anti‐tumor immunity. They capture dead tumor cell‐associated antigens and transfer their information to lymphocsytes, including CD8⁺ T cells, which is important for successful tumor suppression. This study aimed to determine the prognostic significance of CD169⁺ macrophages residing in the tumor‐draining lymph nodes from cases of bladder cancer. In this retrospective study, 44 bladder cancer patients who received radical cystectomy were examined. The abundance of CD169⁺ macrophages in the regional lymph nodes and the number of CD8⁺ T cells in the primary tumor were investigated by immunohistochemistry. A CD169 score was calculated based on the intensity of CD169 staining and the proportion of CD169⁺ macrophages, and the scores were compared to the patients’ clinicopathological parameters. A high CD169 score was significantly associated with low T stage and with a high number of CD8⁺ T cells infiltrating into the tumor. The group with high CD169 expression had significantly longer cancer‐specific survival than the group with low CD169 expression (5‐year cancer‐specific survival rate: 83.3% vs 31.3%). In a multivariate analysis, the CD169 score was identified as a strong and independent favorable prognostic factor for cancer‐specific survival. Our findings suggest that CD169⁺ macrophages in the lymph nodes enhance anti‐tumor immunity by expanding CD8⁺ T cells in bladder cancer. The CD169 score may serve as a novel marker for the evaluation of bladder cancer prognosis.

Phenotypic differences in tumor-associated macrophages between metastatic and primary sites of clear cell renal cell carcinoma

105

Background: Tumor-associated macrophages (TAMs) are one of the key contributors to the tumor microenvironment and are phenotypically differentiated into M1 and M2 macrophages. M1 macrophages stimulate anti-tumor immune responses, whereas M2 macrophages promote immunosuppression and are associated with tumor progression in clear cell renal cell carcinoma (ccRCC). However, little information is available regarding the difference in TAM polarization between primary and metastatic lesions of ccRCC. Methods: We collected paired samples of primary and matched metastatic sites from the first recurrence in 41 metastatic ccRCC patients. Immunohistochemistry (IHC) for Iba1, which is a common pan-macrophage marker, and CD163 and CD204, which are considered to be M2 macrophage markers, was performed on all paired samples. Results: Thirty-three paired primary and metastatic samples were available for IHC assessment in this analysis. The most common metastatic sites were lung (N = 26, 78.8 %) and lymph node (N = 3, 9.1 %). The mean (± standard deviation) cell density of Iba1+ TAMs was higher in metastatic lesions than in primary lesions (756 ± 267 mm2 vs. 581 ± 155 mm2, P = 0.0012). By contrast, the ratio of CD163+ and CD204+ to Iba1+ TAMs was significantly lower in metastatic lesions than in primary lesions (0.76 ± 0.30 vs. 0.90 ± 0.24, P = 0.0067 and 0.39 ± 0.27 vs. 0.67 ± 0.29, P = 0.0001, respectively). The median overall survival of patients with high- vs. low-density Iba1+, CD163+, and CD204+ TAMs in metastatic lesions was 120 vs. 92 months (log-rank P = 0.67), 120 vs. 58 months (log-rank P = 0.056), and 120 vs. 92 months (log-rank P = 0.35), respectively. Conclusions: TAMs in the metastatic lesions of ccRCC polarized towards an M1-like phenotype, although the total number of TAMs was greater in metastatic compared with primary lesions. The cell density of Iba1+, CD163+, and CD204+ TAMs in metastatic sites was not associated with overall survival in patients with ccRCC.

Phenotypical change of tumor-associated macrophages in metastatic lesions of clear cell renal cell carcinoma

Macrophages are the main immune cells of the tumor microenvironment in clear cell renal cell carcinoma (ccRCC). A high density of CD163⁺ or CD204⁺ tumor-associated macrophages (TAMs), rather than the density of total TAMs, is known to be linked to poor clinical outcome. In the present study, we investigated the phenotypical differences between the paired primary and metastatic lesions in ccRCC cases. Using immunostaining, the densities of CD163⁺ and CD204⁺ TAMs in metastatic lesions were found to be significantly lower compared to primary lesions, although the total number of TAMs was increased in metastatic lesions. Since CD163 and CD204 are considered to be the markers of an M2/protumor phenotype in macrophages, TAMs in metastatic lesions are suggested to have a greater M1/inflammatory function compared with those from primary lesions. These findings give new insights in regard to the immunological status of metastatic lesions of ccRCC.

Contrasting effects of cyclophosphamide on anti-CTL-associated protein 4 blockade therapy in two mouse tumor models

Immune checkpoint blockade is a promising anticancer therapy, but must be used in combination with other anticancer therapies to increase its therapeutic efficacy. Cyclophosphamide (CP) is a chemotherapeutic drug that shows immune‐modulating effects. In this study, we examined the effect of CP on anti‐CTL‐associated protein 4 (CTLA‐4) blockade therapy in two mouse tumor models. Drastic tumor regression was observed in the CT26 colon carcinoma model after i.p. injection of CP (100 mg/kg) followed by anti‐CTLA‐4 antibody. However, administration in the reverse order increased apoptosis in tumor‐specific CD8⁺ T cells. In the RENCA renal carcinoma model, the antitumor effect of combination therapy was marginal and the tumor‐bearing state reduced body weight with an increased serum level of interleukin‐6. Interestingly, although CP monotherapy increased myeloid‐derived suppressor cells (MDSCs) in the spleens of both models, subsequent anti‐CTLA‐4 therapy increased MDSCs only in RENCA‐bearing mice. Additionally, the serum levels of chemokine ligand 2 and C‐X‐C motif chemokine 10 were increased by the combination therapy only in RENCA‐bearing mice and in vivo depletion of Gr‐1⁺ cells augmented the antitumor effect to some degree. These results reveal a contrasting effect of CP on anti‐CTLA‐4 therapy between the two mouse tumor models. Cyclophosphamide augments the antitumor effect of anti‐CTLA‐4 therapy in CT26‐bearing hosts, whereas CP after anti‐CTLA‐4 therapy attenuates this effect through induction of apoptosis in tumor‐reactive T cells. Alternatively, CP‐induced MDSCs can be increased by anti‐CTLA‐4 therapy only in RENCA‐bearing hosts with an elevated level of interleukin‐6.

Temsirolimus-induced interstitial lung disease as an on-target effect in patients with metastatic renal cell carcinoma

e16086

Background: An inhibitor for mammalian target of rapamycin (mTORi), temsirolimus, has been used for metastatic renal cell carcinoma (mRCC) pts with poor risk. mTOR is known to regulate proliferation of lymphocytes, which has been rationale of applying mTORi for preventing graft rejection in transplantation. However, nobody knows the immune status of mRCC pts treated with temsirolimus. In addition, accumulation of clinical practices of temsirolimus has revealed a variety of AEs including interstitial lung disease (ILD). The underlying mechanisms of ILD by mTORi remain uncertain. Moreover, the clinical impact of ILD on the clinical response to mTORi remains unknown. So, we have conducted a prospective clinical trial investigating immune parameters in mRCC pts treated with temsirolimus. This project was denominated in Japanese m-TOR Immune Modulation trial (J-TORIM) (UMIN000009662). Methods: J-TORIM was a prospective observational study recruited pts at 25 hospitals in Japan with a targeted sample size of 30. The primary objective was to evaluate whether administration of temsilorimus has consistent effects on immune parameters collected from the peripheral blood before and 3-to-5 weeks after the beginning of temsirolimus therapy. The secondary objectives were to evaluate the associations of immune parameters or ILD with ORR, PFS, and OS, and the associations of immune parameters with ILD. Immune parameters include PBMC culture with con A or lipopolysaccharide (LPS), PBMC flow cytometry with anti- CD4, CD8, CD3, PD-1, PD-L1, CD25, Foxp3 mAbs. Results: Twenty-eight patients were enrolled in the study. ORR of temsirolimus was 10.7% (1 CR and 2 PR). The most commonly reported treatment-related AEs were ILD (28.5%) and stomatitis (28.5%). There were no significant changes after temsirolimus therapy for any immunological parameters. Interestingly, a significant correlation between ILD development and ORR was observed (p < 0.01). In addition, a significant increase of regulatory T cells was also observed after the recovery of ILD (p < 0.05). Conclusions: This is the first prospective study demonstrating that ILD development can be predictive for response to temsirolimus in mRCC pts. Clinical trial information: 000009662.

PD-L1 expression in papillary renal cell carcinoma

Background

The immune escape or tolerance of cancer cells is considered to be closely involved in cancer progression. Programmed death-1 (PD-1) is an inhibitory receptor expressed on activating T cells, and several types of cancer cells were found to express PD-1 ligand 1 (PD-L1) and ligand 2 (PD-L2).

Methods

In the present study, we investigated PD-L1/2 expression in papillary renal cell carcinoma (pRCC).

Result

We found PD-L1 expression in 29 of 102 cases, but no PD-L2 expression was seen. PD-L1 expression was not significantly correlated with any clinicopathological factor, including progression-free survival and overall survival. The frequency of PD-L1-positive cases was higher in type 2 (36%) than in type 1 (22%) pRCC; however, there was no significant difference in the percentages of score 0 cases (p value = 0.084 in Chi-square test). The frequency of high PD-L1 expression cases was higher in type 2 (23%) than in type 1 (11%), and the frequency of high PD-L1 expression cases was higher in grade 3/4 (21%) than in grade 1/2 (13%). However, no significant association was found between PD-L1 expression and all clinicopathological factors in pRCC.

Conclusion

High expression of PD-L1 in cancer cells was potentially associated to highly histological grade of malignancy in pRCC. The evaluation of the PD-L1 protein might still be useful for predicting the efficacy of anti-cancer immunotherapy using immuno-checkpoint inhibitors, however, not be useful for predicting the clinical prognosis.

Electronic supplementary material

The online version of this article (doi:10.1186/s12894-016-0195-x) contains supplementary material, which is available to authorized users.

Infiltration of tumor-associated macrophages is involved in CD44 expression in clear cell renal cell carcinoma

Cancer stem‐like cells (CSC) or cancer‐initiating cells are now considered to be an important cell population related to cancer recurrence and the resistance to anti‐cancer therapy. Tumor‐associated macrophages (TAM) are a main component of stromal cells and are related to cancer progression in clear cell renal cell carcinoma (ccRCC). Because the detailed mechanisms allowing the maintenance of CSC in cancer tissues remain unclear, we investigated the relationship between TAM and CD44‐expressing cancer cells in ccRCC. CD44 was used as a marker for CSC, and CD163 and CD204 were used as markers for TAM. CD44‐positive cancer cells were detected in 37 of the 103 cases. Although statistical analysis showed no relationship between CD44‐positive cancer cells and the clinical course, the distribution of CD44‐positive cancer cells was significantly associated with a high density of TAM. Our in vitro study using RCC cell lines and human macrophages demonstrated that CD44 expression was upregulated by direct co‐culture with macrophages. Silencing of TNF‐alpha on macrophages abrogated the upregulation of CD44 expression in cancer cells. Macrophage‐induced CD44 overexpression was also suppressed by NF‐κB inhibitors. These results suggest that TNF‐alpha derived from TAM is linked to CD44 overexpression via NF‐κB signaling in ccRCC.

CXCL10 and CCL2 mRNA expression in monocytes is inversely correlated with the HLA-DR lower fraction of monocytes in patients with renal cell carcinoma

Circulating cluster of differentiation (CD)14+ human leukocyte antigen (HLA)-DRlow/- monocytes, those with a lower HLA-DR expression or are negative for HLA-DR, are considered to be involved in systemic immunosuppression in patients with several malignant tumors. However, few studies have investigated in detail the gene expression profile of CD14+HLA-DRlow/- monocytes. In the present study, the mRNA expression levels of immune-associated molecules in CD14+ monocytes isolated from healthy donors and patients with renal cell carcinoma (RCC) were analyzed. Consistent with previous studies, the percentage of HLA-DRlow/- cells in CD14+ monocytes was significantly increased in patients with RCC compared with healthy donors. In 3 of the 4 patients who underwent surgical resection of the primary tumor, the percentage of CD14+HLA-DRlow/- cells was significantly decreased following surgery. The mRNA expression levels of cyclooxygenase 2, transforming growth factor β, interleukin 6R, chemokine (C-C motif) ligand 2 (CCL2), chemokine (C-X-C motif) ligand 10 (CXCL10), oncostatin M, and vascular endothelial growth factor-A in CD14+ monocytes were quantified using reverse transcription-quantitative polymerase chain reaction. The results of the present study revealed that increased expression levels of CCL2 and CXCL10 were inversely correlated with the percentage of CD14+HLA-DRlow/- monocytes. This suggested that monocytes in RCC patients were immunologically suppressed, and that immunosuppression in RCC patients may be due, in part, to the dysfunction of circulating monocytes.

Prognostic Significance of CD169+ Lymph Node Sinus Macrophages in Patients with Malignant Melanoma

CD169 (sialoadhesin) is a sialic acid receptor that is specifically expressed on macrophages, including lymph node sinus macrophages. Animal studies suggest that CD169(+) macrophages in lymph nodes have properties in preventing cancers. In order to determine the significance of CD169(+) macrophages in patients with malignant melanoma, we evaluated tissue samples from 93 patients to investigate CD169 expression in regional lymph nodes (RLN) and determine the relationship of this expression with overall survival and various clinicopathologic factors. Higher densities of CD169(+) cells were significantly associated with longer overall survival (P = 0.001). A multivariate analysis showed that the density of CD169(+) cells was an independent prognostic factor, with higher densities correlating with higher density of CD8(+) cytotoxic T cells within tumor sites. High CD169 expression in macrophages could be stimulated by IFNα in vitro, and in RLNs, IFNα-producing macrophages and CD303(+) plasmacytoid dendritic cells were identified surrounding CD169(+) macrophages. These data suggest that IFNα-stimulated CD169(+) macrophages in RLNs are closely involved in T-cell-mediated antitumor immunity and may be a useful marker for assessing the clinical prognosis and monitoring antitumor immunity in patients with malignant melanoma.

Abstract 1276: CD169-positive sinus macrophages in regional lymph nodes are associated with better survival in patients with malignant melanoma

CD169 (sialoadhesin) is a sialic acid receptor that is expressed on the particular macrophages such as lymph node sinus macrophages. Animal studies suggested that CD169+ macrophages in lymph nodes have tumor-preventing properties, but the role of these cells in human tumors has not been clarified. Therefore, we speculated that CD169+ macrophages in regional lymph nodes (RLNs) are suggested to be essential to the anti-tumor immunity and involved in the prognosis of cancer patients. To determine the significance of CD169+ macrophages in patients with malignant melanoma (MM), we examined the expression of CD169 in paraffin-embedded tissue samples from 93 patients by immunohistochemistry and their relationship with overall survival and clinicopathological factors. A high density of CD169+ cells was significantly associated with longer overall survival in patients with MM (P = 0.001). Multivariate analysis showed that the density of CD169+ cells was an independent prognostic factor. We also found that the density of CD169+ macrophage was positively correlated with the number of CD8+ cytotoxic T cells infiltrating into tumor tissues. Furthermore, interferon (IFN)-α induced strong CD169 expression on human macrophages in vitro, and IFN-α-producing cells were indeed detected surrounding CD169+ cells in lymph node. Our data support that IFN-α-producing cells may be plasmacytoid dendritic cells (pDCs) known to produce IFN-α. These results suggest that CD169+ macrophages in RLNs are intimately involved in T-cell-mediated antitumor immunity and may be a helpful marker for assessing clinical prognosis and monitoring antitumor immunity in patients with MM.

Citation Format: Yoichi Saito, Koji Ohnishi, Azusa Miyashita, Satoshi Nakahara, Yukio Fujiwara, Hasita Horlad, Takanobu Motoshima, Satoshi Fukushima, Masatoshi Jinnin, Hironobu Ihn, Motohiro Takeya, Yoshihiro Komohara. CD169-positive sinus macrophages in regional lymph nodes are associated with better survival in patients with malignant melanoma. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 1276. doi:10.1158/1538-7445.AM2015-1276

C5aR is frequently expressed in metastatic renal cell carcinoma and plays a crucial role in cell invasion via the ERK and PI3 kinase pathways

The anaphylatoxin C5a is a chemoattractant for leukocyte migration via the C5a receptor (C5aR). We recently reported that C5aR was aberrantly expressed in a wide variety of human related cancers, while it also promotes cancer cell invasion by C5a stimulation. However, the biological significance of C5aR expression in renal cell carcinoma (RCC) has not yet been clarified. In the present study, we aimed to elucidate the biological role of C5aR in RCC progression. Clinical RCC specimens were analyzed for C5aR expression and its relationship with baseline demographic data and clinicopathological parameters was analyzed. Moreover, renal carcinoma Renca cells stably expressing C5aR were generated and used to assess the effects of C5a-C5aR axis activation on various cellular phenomena in culture. Immunohistochemistry revealed that 96.7% of the metastatic RCCs (mRCCs) showed C5aR expression, whereas only 50.5% of the non-metastatic RCCs expressed C5aR (P<0.001). Although C5a stimulation did not significantly alter anoikis of C5aR‑expressing Renca cells, C5a elicited cell morphological change and scattering of those cells accompanied with dynamic actin rearrangement, which was not observed in the Renca cells harboring the empty vector only. Moreover, C5a triggered ERK and PI3K‑dependent invasion of the C5aR-expressing renal carcinoma cells. These results are consistent with the idea that the C5a-C5aR axis plays a crucial role in renal carcinoma cell invasion, which may be one of the key steps for RCC metastasis. The present study provides proof‑of‑concept that the C5a-C5aR axis may be a useful therapeutic target for preventing RCC progression.

[Efficacy and safety of maintenance intravesical instillation therapy with bacillus Calmette-Guerin and epirubicin for non-muscle invasive bladder cancer]

The objectives of this study were to evaluate the efficacy and toxicity of maintenance intravesical instillation therapy with bacillus Calmette-Guerin (BCG) and epirubicin for non-muscle invasive bladder cancer. From April 1999 to March 2010, 27 eligible patients were enrolled in this study. After receiving one cycle of epirubicin (100 mg/100 ml) by intravesical instillation, all patients received 6 weekly alternate intravesical instillation of BCG (80 mg/50 ml) and epirubicin (50 mg/50 ml), followed by 10 monthly instillations. Among the 27 patients, 19 were men and 8 were women, with a median age of 62.4 years (range, 37-78 years). Tumor pathologic stage was pTa in 25 patients, pT1 in 2 and there were no concomitant carcinoma in situ cases. Median follow-up was 37.1 months (range, 11-82 months). The 3- year recurrence-free and progression-free survival rates were 75.3% and 96.1%, respectively. Furthermore, a high completion rate of 81.5% was achieved in this study. Adverse events of grade 3 or higher occurred in 3 patients (11.1%), 1 patient had anaphylaxis. There were no treatment-related deaths. Maintenance intravesical instillation therapy with BCG and epirubicin is a favorable therapeutic option for non-muscle invasive bladder cancer. Given the safety and benefit profile found in this study, appropriate patient selection is warranted in the future.

[Initial division of the left renal vein before dissection of left renal vein occluded by intracaval tumor thrombus]

Between November 2008 and March 2010, we performed initial division of the left renal vein occluded by the tumor thrombus in six cases of left renal cancer at Toranomon Hospital. The left renal vein was completely occluded by the tumor thrombus in all cases. In order to ligate the left renal artery first behind the dilated left renal vein, we must dissect the left kidney with arterial blood flow. Massive bleeding from the numerous engorged collateral veins around the left kidney is inevitable. Furthermore, access to the left renal artery is difficult because of the large tumor. We therefore initially divided the left renal vein without arterial blood flow followed by division of the left renal artery. After nephrectomy by dissecting the tumor without blood flow we extirpated the intracaval tumor thrombus. The median time of the operation was 7 hours 35 minutes and the median amount of blood loss was 2,869 ml. The tumor stage was pT3b in four cases and pT3c in two cases. No complications were observed during and after surgery except for one case of lymphocele and another case of chylous ascites. The initial division of the left renal vein is considered to be a useful surgical approach in left renal cancer with occluded left renal vein, especially when the tumor is large.

[The initial division of left renal vein in left renal cancer with intracaval tumor thrombus: a case report]

A 30-year-old female was admitted to our hospital with a 3-month history of general fatigue and one month history of left flank mass. Computed tomography revealed a huge left renal tumor (20 × 13 × 10 cm) with intracaval tumor thrombus. The tumor thrombus extended into the right atrium. The left renal vein (lt-RV) was expanded 3.5 cm in diameter by the tumor thrombus. The tumor was surrounded by a tortuous dilated capsular vein. The strategic issue was how to ligate the left renal artery (lt-RA) behind the expanded lt-RV. We first divided the lt-RV occluded by the tumor thrombus using a Linear Cutter® and then divided the lt-RA before the dissection of the tumor to avoid excessive bleeding. Even transarterial embolization of lt-RA were to be performed,the tumor was too large to dissect without division of lt-RV and lt RA. After the left kidney was removed,the lower half of the tumor thrombus was excised,clamping the inferior vena cava,three right renal arteries,two right renal veins,and the lumber vein. Finally,we removed the upper half of the tumor thrombus extending to the right atrium through atriotomy and cavotomy under an extracorporeal cardiovascular bypass. Operation time was 9 h 22 m,and total blood loss was 1670 ml. Convalescence was uneventful except for abdominal lymphocele.