Tyrosine kinase inhibitors reprogramming immunity in renal cell carcinoma: rethinking cancer immunotherapy

Construction and validation of programmed cell death-based molecular clusters for prognostic and therapeutic significance of clear cell renal cell carcinoma

As the dominant histological subtype of kidney cancer, clear cell renal cell carcinoma (ccRCC) poorly responds to conventional chemotherapy and radiotherapy. Although novel immunotherapies such as immune checkpoint inhibitors could have a durable effect in treating ccRCC patients, the limited availability of dependable biomarkers has restricted their application in clinic. In the study of carcinogenesis and cancer therapies, there has been a recent emphasis on researching programmed cell death (PCD). In the current study, we discovered the enriched and prognostic PCD in ccRCC utilizing gene set enrichment analysis (GSEA) and investigate the functional status of ccRCC patients with different PCD risks. Then, genes related to PCD that had prognostic value in ccRCC were identified for the conduction of non-negative matrix factorization to cluster ccRCC patients. Next, the tumor microenvironment, immunogenicity, and therapeutic response in different molecular clusters were analyzed. Among PCD, apoptosis and pyroptosis were enriched in ccRCC and correlated with prognosis. Patients with high PCD levels were related to poor prognosis and a rich but suppressive immune microenvironment. PCD-based molecular clusters were identified to differentiate the clinical status and prognosis of ccRCC. Moreover, the molecular cluster with high PCD levels may correlate with high immunogenicity and a favorable therapeutic response to ccRCC. Furthermore, a simplified PCD-based gene classifier was established to facilitate clinical application and used transcriptome sequencing data from clinical ccRCC samples to validate the applicability of the gene classifier. We thoroughly extended the understanding of PCD in ccRCC and constructed a PCD-based gene classifier for differentiation of the prognosis and therapeutic efficacy in ccRCC.

YAP-Activated SATB2 Is a Coactivator of NRF2 That Amplifies Antioxidative Capacity and Promotes Tumor Progression in Renal Cell Carcinoma

Aberrant epigenetic reprogramming contributes to the progression of renal cell carcinoma (RCC). Elucidation of key regulators of epigenetic reprogramming in RCC could help identify therapeutic vulnerabilities to improve treatment. Here, we report upregulation of the nuclear matrix-associated protein, special AT-rich binding protein-2 (SATB2), in RCC samples, which correlated with poor prognosis. SATB2 inhibition suppressed RCC growth and self-renewal capacities. YAP/TEAD4 activated SATB2 expression and depended on SATB2 to enhance cell proliferation. Transcriptome analysis implicated that SATB2 regulates NRF2 downstream targets to suppress oxidative stress without altering NRF2 levels. Integrated chromatin immunoprecipitation sequencing and assay for transposase-accessible chromatin using sequencing analyses demonstrated that SATB2 coordinated with NRF2 to drive enhancer-promoter interactions, amplifying transcriptional activity. SATB2 recruited SWI/SNF complex subunits, including BRD7 or BRG1, to sustain DNA accessibility. Increased SATB2 triggered chromatin remodeling into configurations that rendered RCC more sensitive to SATB2 deficiency. Moreover, SATB2 ablation promoted the sensitivity of RCC to chemotherapy-induced apoptosis. Finally, targeting SATB2 or BRD7 effectively restricted the proliferation of YAP-high tumors in patient-derived xenografts and patient-derived organoids. Together, SATB2 is an oncogenic chromatin organizer in RCC, and targeting SATB2 is an effective strategy to suppress the YAP-high RCC.

SIGNIFICANCE

A YAP-SATB2-NRF2 regulatory axis amplifies antioxidative stress signaling and provides potential therapeutic targets to enhance response to chemotherapy in renal cell carcinoma.

Synergistic effect of combining sunitinib with a peptide-based vaccine in cancer treatment after microenvironment remodeling

Although it has proven difficult to demonstrate the clinical efficacy of therapeutic vaccination as a monotherapy in advanced cancers, its combination with an immunomodulatory treatment to reduce intra-tumor immunosuppression and improve vaccine efficacy is a very promising strategy. In this context, we are studying the combination of a vaccine composed of peptides of the tumor antigen survivin (SVX vaccine) with the anti-angiogenic agent sunitinib in a colorectal carcinoma model. To this end, we have been focusing on administration scheduling and have highlighted a therapeutic synergy between SVX vaccine and sunitinib when the vaccine was administered at the end of anti-angiogenic treatment. In this setting, a prolonged control of tumor growth associated with an important percentage of complete tumor regression was observed. Studying the remodeling induced by each therapy on the immunological and angiogenic tumor microenvironment over time we observed, during sunitinib treatment, a transient increase in polymorphonuclear myeloid-derived suppressor cells (PMN-MDSCs) and a decrease in NK cells in the tumor microenvironment. In contrast, after sunitinib treatment was stopped, a decrease in PMN-MDSC populations has been observed in the tumor, associated with an increase in NK cells, pericyte coverage of tumor vessels and CD8⁺ T cell population and functionality. In conclusion, sunitinib treatment results in the promotion of an immune-favorable tumor microenvironment that can guide the optimal sequence of vaccine and anti-angiogenic combination to reinforce their synergy.

Molecular mechanisms of resistance to tyrosine kinase inhibitor in clear cell renal cell carcinoma

Clear cell renal cell carcinoma (ccRCC) is the most common subtype of renal cell carcinoma (RCC). Loss of von Hippel-Lindau tumor suppressor gene is frequently observed in ccRCC and increases the expression of hypoxia-inducible factors and their targets, including epidermal growth factor, vascular endothelial growth factor, and platelet-derived growth factor. Tyrosine kinase inhibitors (TKIs) offer a survival benefit in metastatic renal cell carcinoma (mRCC). Recently, immune checkpoint inhibitors have been introduced in mRCC. Combination therapy with TKIs and immune checkpoint inhibitors significantly improved patient outcomes. Therefore, TKIs still play an essential role in mRCC treatment. However, the clinical utility of TKIs is compromised when primary and acquired resistance are encountered. The mechanism of resistance to TKI is not fully elucidated. Here, we comprehensively reviewed the molecular mechanisms of resistance to TKIs and a potential strategy to overcome this resistance. We outlined the involvement of angiogenesis, non-angiogenesis, epithelial-mesenchymal transition, activating bypass pathways, lysosomal sequestration, non-coding RNAs, epigenetic modifications and tumor microenvironment factors in the resistance to TKIs. Deep insight into the molecular mechanisms of resistance to TKIs will help to better understand the biology of RCC and can ultimately help in the development of more effective therapies.

Atezolizumab plus tivozanib for immunologically cold tumor types: the IMMCO-1 trial

Immune checkpoint inhibitor therapy represents a significant advance in cancer care. The interaction between PD-1 and PD-L1 induces immune tolerance and the inhibition of this interaction is an effective treatment strategy for numerous malignancies. Despite its demonstrated potential, immunotherapy is not clinically effective in immunogenically 'cold' tumors such as pancreatic cancer, prostate cancer and neuroendocrine tumors. Through the inhibition of VEGF, it may be possible to potentiate the effect of immune checkpoint blockade in tumors that have traditionally shown a lack of clinical response to immunotherapy. This signal-seeking, single-arm, prospective clinical trial aims to determine the objective response of tivozanib and atezolizumab in advanced immunogenically cold solid tumors. Clinical Trial Registration: NCT05000294 (ClinicalTrials.gov).

Identifying tumor antigens and immune subtypes of renal cell carcinoma for immunotherapy development

Renal cell carcinoma (RCC) is one of the leading causes of death in men. Messenger ribonucleic acid (mRNA) vaccines may be an attractive means to achieve satisfactory results. Cancer immunotherapy is a promising cancer treatment strategy. However, immunotherapy is not widely used in renal cell carcinoma, as only a few patients show a positive response. The present study aimed to identify potential antigens associated with renal cell carcinoma to develop an anti-renal cell carcinoma mRNA vaccine. Moreover, the immune subtypes of renal cell carcinoma cells were determined. The Cancer Genome Atlas (TCGA) analysis revealed gene expression profiles and clinical information. Antigen-presenting cells infiltrated the immune system using Tumor Immune Estimation Resource (TIMER) tool (http://timer.cistrome.org/). GDSC (Genomics of Drug Sensitivity in Cancer) database were used to estimate drug sensitivity. The 13 immune-related genes discovery could be targets for immunotherapy in renal cell carcinoma patients, as they were associated with a better prognosis and a higher level of antigen-presenting cells. These immune subtypes have significant relationships with immunological checkpoints, immunogenic cell death regulators, and RCC prognostic variables. Furthermore, DBH-AS1 was identified as a potential antigen for developing an mRNA vaccine. The CCK8 assay demonstrated that the proliferative capacity of 786-O and Caki-1 cells overexpressing DBH-AS1 was higher than in the control group. In addition, transwell assay revealed that 786-O and Caki-1 cells overexpressing DBH-AS1 showed higher invasion capacity compared with control. This study provides a theoretical basis for the development of mRNA vaccines. Our findings suggest that DBH-AS1 could be potential antigens for developing RCC mRNA vaccines.

Combining immune checkpoint inhibition plus tyrosine kinase inhibition as first and subsequent treatments for metastatic renal cell carcinoma

Background

Immune checkpoint inhibitor/tyrosine kinase inhibitor (ICI/TKI) combinations are a new standard of care for the initial treatment of metastatic renal cell carcinoma (mRCC). Their efficacy and toxicity beyond the first‐line setting remain poorly defined.

Methods

We retrospectively reviewed charts for 85 adults with mRCC of any histology receiving combination of ICI/TKI in any line of treatment at two academic centers as of 05/01/2020. We collected clinical, pathological, and treatment‐related variables. Outcomes including objective response rate (ORR), progression‐free survival (PFS), and toxicity were analyzed via descriptive statistics and the Kaplan–Meier method.

Results

Patients received pembrolizumab, nivolumab, avelumab, or nivolumab–ipilimumab, with concurrent use of sunitinib, axitinib, pazopanib, lenvatinib, or cabozantinib. Thirty‐three patients received first‐line ICI/TKI therapy, while 52 received ≥ second‐line ICI/TKI. The efficacy of ICI/TKI therapy decreased with increasing lines of treatment (ORR: 56.7%, 37.5%, 21.4%, and 21%; median PFS [mPFS]: 15.2, 14.2, 10.1, and 6.8 months, for first, second, third, and ≥ fourth line therapy, respectively). In the ≥ second‐line setting, ICI/TKI was most useful in patients who received ICI only, with an ORR of 50% and a mPFS of 9.1 months. Efficacy was limited in patients who received both TKI and ICI previously, with an ORR of 20% and a mPFS of 5.5 months. Overall, ≥ second‐line ICI/TKI was tolerable with 25 of 52 (52%) patients developing grade ≥3 adverse events.

Conclusions

ICI/TKI combination therapy is feasible and safe beyond the first‐line setting. Prior treatment history appears to impact efficacy but has a lesser effect on safety/tolerability.

Microphysiological model of the renal cell carcinoma to inform anti-angiogenic therapy

Renal cell carcinomas are common genitourinary tumors characterized by high vascularization and strong reliance on glycolysis. Despite the many available therapies for renal cell carcinomas, first-line targeted therapies, such as cabozantinib, and durable reaponses are seen in only a small percentage of patients. Yet, little is known about the mechanisms that drive response (or lack thereof). This dearth of knowledge can be explained by the dynamic and complex microenvironment of renal carcinoma, which remains challenging to recapitulate in vitro. Here, we present a microphysiological model of renal cell carcinoma, including a tubular blood vessel model of induced pluripotent stem cell-derived endothelial cells and an adjacent 3D carcinoma model. Our model recapitulated hypoxia, glycolic metabolism, and sprouting angiogenesis. Using our model, we showed that cabozantinib altered cancer cell metabolism and decreased sprouting angiogenesis but did not restore barrier function. This microphysiological model could be helpful to elucidate, through multiple endpoints, the contributions of the relevant environmental components in eliciting a functional response or resistance to therapy in renal cell carcinoma.

Immunogenic Cell Death and Immunomodulatory Effects of Cabozantinib

Cabozantinib (XL-184) is a multitarget tyrosine kinase inhibitor (TKI) targeting receptor tyrosine kinases (RTKs) involved in oncogenesis and angiogenesis. It is currently the standard therapy for medullary thyroid cancer (MTC), metastatic renal cell carcinoma (mRCC), and hepatocellular carcinoma (HCC). Combination of Cabozantinib with immunotherapy is now a standard treatment in metastatic renal cancer, and its efficacy is being tested in ongoing clinical trial in prostate cancer patients. Here, we report that Cabozantinib may exert an immunostimulatory role by inducing immunogenic stress of prostate cancer cells and directly modulating dendritic cells (DCs). Cabozantinib treatment arrested the cell cycle and triggered immunogenic cell death (ICD) in prostate cancer cells in vitro. Cabozantinib had a direct effect on DCs by the down-modulation of β-catenin and change in migratory and costimulatory phenotype of the DCs. These results may suggest possible immunomodulatory effects induced by Cabozantinib that could be exploited to optimize patient-tailored immunotherapeutic treatments.

Identification of an independent immune-genes prognostic index for renal cell carcinoma

Background

Considerable evidence has indicated an association between the immune microenvironment and clinical outcome in ccRCC. The purpose of this study is to extensively figure out the influence of immune-related genes of tumors on the prognosis of patients with ccRCC.

Methods

Files containing 2498 immune-related genes were obtained from the Immunology Database and Analysis Portal (ImmPort), and the transcriptome data and clinical information relevant to patients with ccRCC were identified and downloaded from the TCGA data-base. Univariate and multivariate Cox regression analyses were used to screen out prognostic immune genes. The immune risk score model was established in light of the regression coefficient between survival and hub immune-related genes. We eventually set up a nomogram for the prediction of the overall survival for ccRCC. Kaplan-Meier (K-M) and ROC curve was used in evaluating the value of the predictive risk model. A P value of < 0.05 indicated statistically significant differences throughout data analysis.

Results

Via differential analysis, we found that 556 immune-related genes were expressed differentially between tumor and normal tissues (p < 0. 05). The analysis of univariate Cox regression exhibited that there was a statistical correlation between 43 immune genes and survival risk in patients with ccRCC (p < 0.05). Through Lasso-Cox regression analysis, we established an immune genetic risk scoring model based on 18 immune-related genes. The high-risk group showed a bad prognosis in K-M analysis. (p < 0.001). ROC curve showed that it was reliable of the immune risk score model to predict survival risk (5 year over survival, AUC = 0.802). The model indicated satisfactory AUC and survival correlation in the validation data set (5 year OS, Area Under Curve = 0.705, p < 0.05). From Multivariate regression analysis, the immune-risk score model plays an isolated role in the prediction of the prognosis of ccRCC. Under multivariate-Cox regression analysis, we set up a nomogram for comprehensive prediction of ccRCC patients’ survival rate. At last, it was identified that 18 immune-related genes and risk scores were not only tremendously related to clinical prognosis but also contained in a variety of carcinogenic pathways.

Conclusion

In general, tumor immune-related genes play essential roles in ccRCC development and progression. Our research established an unequal 18-immune gene risk index to predict the prognosis of ccRCC visually. This index was found to be an independent predictive factor for ccRCC.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12885-021-08367-6.

Absent in melanoma 2-mediating M1 macrophages facilitate tumor rejection in renal carcinoma

Absent in melanoma 2 (AIM2) as an immune regulator for the regulation of tumor-associated macrophages (TAMs) function is unclear in tumor development. Here, the AIM2 function was investigated in TAMs-mediated malignant behaviors of renal carcinoma. The correlation analysis result showed that the AIM2 expression in TAMs was negatively correlated with the percentages of M2-like polarization phenotype in human or murine renal cancer specimens. By the cocultured assay with bone marrow-derived macrophages (BMDMs) and Renca cells, overexpression of AIM2 in macrophages enhanced the inflammasome activation and reversed the phenotype from M2 to M1. Compared with BMDMs-Ctrl cocultured group, BMDMs-AIM2 cocultured group showed reduced tumor cell proliferation and migration. The blockade of inflammasome activation by the inhibitor Ac-YVAD-CMK abrogated AIM2-mediated M1 polarization and the inhibition of tumor cell growth. To evaluate the therapeutic efficacy of AIM2-mediated M1 macrophages in vivo, BMDMs-AIM2 were intravenously injected into subcutaneous Renca-tumor mice. The results showed that the infiltration of M1 TAMs was increased and tumor growth was suppressed in BMDMs-AIM2-treated mice when compared with BMDMs-Ctrl-treat mice. Accordingly, the blockade of inflammasome activation reduced the anti-tumor activities of BMDMs-AIM2. Moreover, the lung metastases of renal carcinoma were suppressed by the administration of BMDMs-AIM2 accompanied with the reduced tumor foci. These results demonstrated that AIM2 enhanced TAMs polarization switch from anti-inflammatory M2 phenotypy to pro-inflammatory M1 through inflammasome signaling activation, thus exerting therapeutic intervention in renal carcinoma models. Our results provide a possible molecular mechanism for the modulation of TAMs polarization in tumor microenvironment and open a new potential therapeutic approach for renal cancer.

Neo-Fs Index: A Novel Immunohistochemical Biomarker Panel Predicts Survival and Response to Anti-Angiogenetic Agents in Clear Cell Renal Cell Carcinoma

Background: Frameshift indels have emerged as a predictor of immunotherapy response but were not evaluated yet to predict anti-angiogenetic agent (AAA) response or prognosis in clear cell renal cell carcinoma (ccRCC). Methods: Here, to develop biomarkers that predict survival and response to AAA, we evaluated the immunohistochemical expression of proteins whose genes frequently harbor frameshift indels in 638 ccRCC patients and correlated the individual and integrated markers with prognosis and AAA response. The mutational landscape was evaluated using targeted next-generation sequencing in 12 patients concerning protein markers. Immune gene signatures were retrieved from TCGA RNA seq data. Results: Five proteins (APC, NOTCH1, ARID1A, EYS, and filamin A) were independent adverse prognosticators and were incorporated into the Neo-fs index. Better overall, disease-specific and recurrence-free survival were observed with high Neo-fs index in univariate and multivariate survival analyses. Better AAA responses were observed with a high Neo-fs index, which reflected increased MHC class I, CD8+ T cell, cytolytic activity, and plasmacytoid dendritic cell signatures and decreased type II-IFN response signatures, as well as greater single-nucleotide variant (SNV) and indel counts. Conclusions: Neo-fs index, reflecting antitumor immune signature and more SNVs. and indels, is a powerful predictor of survival and AAA response in ccRCC.

Anti-tumor efficacy of human anti-c-met CAR-T cells against papillary renal cell carcinoma in an orthotopic model

Chimeric antigen receptor (CAR)‐T cell therapy has shown salient efficacy in cancer immunotherapy, particularly in the treatment of B cell malignancies. However, the efficacy of CAR‐T for solid tumors remains inadequate. In this study, we displayed that c‐met is an appropriate therapeutic target for papillary renal cell carcinoma (PRCC) using clinical samples, developed an anti‐human c‐met CAR‐T cells, and investigated the anti‐tumor efficacy of the CAR‐T cells using an orthotopic mouse model as pre‐clinical research. Administration of the anti‐c‐met CAR‐T cells induced marked infiltration of the CAR‐T cells into the tumor tissue and unambiguous suppression of tumor growth. Furthermore, in combination with axitinib, the anti‐tumor efficacy of the CAR‐T cells was synergistically augmented. Taken together, our current study demonstrated the potential for clinical application of anti‐c‐met CAR‐T cells in the treatment of patients with PRCC.

Sunitinib Treatment-elicited Distinct Tumor Microenvironment Dramatically Compensated the Reduction of Myeloid-derived Suppressor Cells

BACKGROUND/AIM

The clinical response rate of prostate cancer to tyrosine kinase inhibitor (TKI) monotherapy is low. The mechanisms of resistance to TKI are unclear. This study aimed to examine if the tumor microenvironment (TME) is involved in the resistance.

MATERIALS AND METHODS

The anti-vascular effect of Sutent was examined by immunofluorescent staining in TRAMP-C1 tumor. The percentage of CD11b⁺ population were analyzed by flow cytometry. The level of cytokines and chemokines were measured by multiplex immunoassay.

RESULTS

The Sutent monotherapy caused 1.5 days of tumor growth delay, chronic hypoxia, and more mature vasculature. Sutent monotherapy increased the percentage of polymorphonuclear myeloid-derived suppressor cells (MDSCs) in peripheral blood. The evolved TME triggered the re-distribution of myeloid cells in chronically hypoxic areas. The multiplex immunoassay indicated higher levels of several cytokines and chemokines both in tumors and the blood.

CONCLUSION

Sunitinib treatment induced a distinct tumor microenvironment that impaired the efficient reduction of MDSCs by TKI.

Tryptophan Catabolism as Immune Mechanism of Primary Resistance to Anti-PD-1

Background: Clinical trials showed that only a subset of patients benefits from immunotherapy, suggesting the need to identify new predictive biomarker of resistance. Indoleamine-2,3-dioxygenase (IDO) has been proposed as a mechanism of resistance to anti-PD-1 treatment, and serum kynurenine/tryptophan (kyn/trp) ratio represents a possible marker of IDO activity. Methods: Metastatic non-small cell lung cancer (NSCLC), renal cell carcinoma (RCC), and head and neck squamous cell carcinoma (HNSCC) treated with nivolumab as second-line treatment were included in this prospective study. Baseline serum kyn and trp levels were measured by high-performance liquid chromatography to define the kyn/trp ratio. The χ2-test and t-test were applied to compare frequencies and mean values of kyn/trp ratio between subgroups with distinct clinical/pathological features, respectively. Median baseline kyn/trp ratio was defined and used as cutoff in order to stratify the patients. The association between kyn/trp ratio, clinical/pathological characteristics, response, progression-free survival (PFS), and overall survival (OS) was analyzed. Results: Fifty-five patients were included. Mean baseline serum kyn/trp ratio was significantly lower in female than in male patients (0.048 vs. 0.059, respectively, p = 0.044) and in patients with lung metastasis than in others (0.053 vs. 0.080, respectively, p = 0.017). Mean baseline serum kyn/trp ratio was significantly higher in early progressor patients with both squamous and non-squamous NSCLC (p = 0.003) and with a squamous histology cancer (19 squamous NSCLC and 14 HNSCC, p = 0.029). The median value of kyn/trp ratio was 0.06 in the overall population. With the use of median value as cutoff, patients with kyn/trp ratio > 0.06 had a higher risk to develop an early progression (within 3 months) to nivolumab with a trend toward significance (p = 0.064 at multivariate analysis). Patients presenting a baseline kyn/trp ratio ≤0.06 showed a longer PFS [median 8 vs. 3 months; hazard ratio (HR): 0.49; 95% confidence interval (CI) 0.24-1.02; p = 0.058] and a significantly better OS than did those with a kyn/trp ratio > 0.06 (median 16 vs. 4 months; HR: 0.39; 95% CI 0.19-0.82; p = 0.013). Conclusion: Serum kyn/trp ratio could have both prognostic and predictive values in patients with solid tumor treated with immunotherapy, probably reflecting a primary immune-resistant mechanism regardless of the primary tumor histology. Its relative weight is significantly related to gender, site of metastasis, NSCLC, and squamous histology, although these suggestive data need to be confirmed in larger studies.

Tyrosine Kinase Inhibitors in Cancer: Breakthrough and Challenges of Targeted Therapy

Receptor tyrosine kinases (RTKs) are key regulatory signaling proteins governing cancer cell growth and metastasis. During the last two decades, several molecules targeting RTKs were used in oncology as a first or second line therapy in different types of cancer. However, their effectiveness is limited by the appearance of resistance or adverse effects. In this review, we summarize the main features of RTKs and their inhibitors (RTKIs), their current use in oncology, and mechanisms of resistance. We also describe the technological advances of artificial intelligence, chemoproteomics, and microfluidics in elaborating powerful strategies that could be used in providing more efficient and selective small molecules inhibitors of RTKs. Finally, we discuss the interest of therapeutic combination of different RTKIs or with other molecules for personalized treatments, and the challenge for effective combination with less toxic and off-target effects.

In situ Vaccination by Direct Dendritic Cell Inoculation: The Coming of Age of an Old Idea?

For more than 25 years, dendritic cell (DC) based vaccination has flashily held promises to represent a therapeutic approach for cancer treatment. While the vast majority of studies has focused on the use of antigen loaded DC, the intratumoral delivery of unloaded DC aiming at in situ vaccination has gained much less attention. Such approach grounds on the ability of inoculated DC to internalize and process antigens directly released by tumor (usually in combination with cell-death-inducing agents) to activate broad patient-specific antitumor T cell response. In this review, we highlight the recent studies in both solid and hematological tumors showing promising clinical results and discuss the main pitfalls and advantages of this approach for endogenous cancer vaccination. Lastly, we discuss how in situ vaccination by DC inoculation may fit with current immunotherapy approaches to expand and prolong patient response.

Second line therapy with axitinib after only prior sunitinib in metastatic renal cell cancer: Italian multicenter real world SAX study final results

BACKGROUND

This multi-institutional retrospective real life study was conducted in 22 Italian Oncology Centers and evaluated the role of Axitinib in second line treatment in not selected mRCC patients.

METHODS

148 mRCC patients were evaluated. According to Heng score 15.5%, 60.1% and 24.4% of patients were at poor risk, intermediate and favorable risk, respectively.

RESULTS

PFS, OS, DCR and ORR were 7.14 months, 15.5 months, 70.6% and 16.6%, respectively. The duration of prior sunitinib treatment correlated with a longer significant mPFS, 8.8 vs 6.3 months, respectively. Axitinib therapy was safe, without grade 4 adverse events. The most frequent toxicities of all grades were: fatigue (50%), hypertension (26%), and hypothyroidism (18%). G3 blood pressure elevation significantly correlated with longer mPFS and mOS compared to G1-G2 or no toxicity. Dose titration (DT) to 7 mg and 10 mg bid was feasible in 24% with no statistically significant differences in mPFS and mOS. The sunitinib-axitinib sequence was safe and effective, the mOS was 41.15 months. At multivariate analysis, gender, DCR to axitinib and to previous sunitinib correlated significantly with PFS; whereas DCR to axitinib, nephrectomy and Heng score independently affected overall survival.

CONCLUSIONS

Axitinib was effective and safe in a not selected real life mRCC population. Trial registration INT - Napoli - 11/16 oss. Registered 20 April 2016. http://www.istitutotumori.na.it.

Clinical significance of programmed death-1 and programmed death-ligand 1 expression in the tumor microenvironment of clear cell renal cell carcinoma

Recently, immunotherapy based on blocking immune checkpoints with programmed death-1 (PD-1) or PD-ligand 1 (PD-L1) Abs has been introduced for the treatment of advanced clear cell renal cell carcinoma (ccRCC), especially tumors resistant to vascular endothelial growth factor-tyrosine kinase inhibitors (VEGF-TKIs), but the significance of their expression in the tumor microenvironment is unclear. We investigated these immune checkpoint markers in tumor cells and tumor-infiltrating immune cells (TIIC) in the tumor microenvironment of 100 untreated and 25 VEGF-TKI-treated primary ccRCC tissues. Upregulated expression of PD-1 and PD-L1 by TIIC, and PD-L1 by tumor cells was associated with the histological grade and unfavorable prognosis of RCC patients. High PD-1 and PD-L1 expression by TIIC was associated with a poorer response to VEGF-TKI, whereas PD-L1 expression by tumor cells did not affect the efficacy of the treatment. Furthermore, increased PD-1-positive TIIC and PD-L1-positive TIIC were observed in tumors treated with VEGF-TKIs compared with those in untreated tumors. Our data suggest that PD-1 and PD-L1 expression by TIIC in the tumor microenvironment is involved in treatment resistance, and that sequential therapy with immune checkpoint inhibitors could be a promising therapeutic strategy for ccRCC resistant to VEGF-TKI treatment.

Targeting Tumor Microenvironment for Cancer Therapy

Cancer development is highly associated to the physiological state of the tumor microenvironment (TME). Despite the existing heterogeneity of tumors from the same or from different anatomical locations, common features can be found in the TME maturation of epithelial-derived tumors. Genetic alterations in tumor cells result in hyperplasia, uncontrolled growth, resistance to apoptosis, and metabolic shift towards anaerobic glycolysis (Warburg effect). These events create hypoxia, oxidative stress and acidosis within the TME triggering an adjustment of the extracellular matrix (ECM), a response from neighbor stromal cells (e.g., fibroblasts) and immune cells (lymphocytes and macrophages), inducing angiogenesis and, ultimately, resulting in metastasis. Exosomes secreted by TME cells are central players in all these events. The TME profile is preponderant on prognosis and impacts efficacy of anti-cancer therapies. Hence, a big effort has been made to develop new therapeutic strategies towards a more efficient targeting of TME. These efforts focus on: (i) therapeutic strategies targeting TME components, extending from conventional therapeutics, to combined therapies and nanomedicines; and (ii) the development of models that accurately resemble the TME for bench investigations, including tumor-tissue explants, “tumor on a chip” or multicellular tumor-spheroids.

Transcriptomic Profiling of the Tumor Microenvironment Reveals Distinct Subgroups of Clear Cell Renal Cell Cancer: Data from a Randomized Phase III Trial

Metastasis remains the main reason for renal cell carcinoma (RCC)-associated mortality. Tyrosine kinase inhibitors (TKI) impart clinical benefit for most patients with RCC, but the determinants of response are poorly understood. We report an integrated genomic and transcriptomic analysis of patients with metastatic clear cell RCC (ccRCC) treated with TKI therapy and identify predictors of response. Patients in the COMPARZ phase III trial received first-line sunitinib or pazopanib with comparable efficacy. RNA-based analyses revealed four distinct molecular subgroups associated with response and survival. Characterization of these subgroups identified mutation profiles, angiogenesis, and macrophage infiltration programs to be powerful predictors of outcome with TKI therapy. Notably, predictors differed by the type of TKI received. Our study emphasizes the clinical significance of angiogenesis and immune tumor microenvironment and suggests that the critical effects its various aspects have on TKI efficacy vary by agent. This has broad implications for optimizing precision treatment of RCC. SIGNIFICANCE: The determinants of response to TKI therapy in metastatic ccRCC remain unknown. Our study demonstrates that key angiogenic and immune profiles of the tumor microenvironment may affect TKI response. These findings have the potential to inform treatment personalization in patients with RCC.This article is highlighted in the In This Issue feature, p. 453.

Epithelial Membrane Protein-2 (EMP2) Antibody Blockade Reduces Corneal Neovascularization in an In Vivo Model

Purpose

Pathologic corneal neovascularization is a major cause of blindness worldwide, and treatment options are currently limited. VEGF is one of the critical mediators of corneal neovascularization but current anti-VEGF therapies have produced limited results in the cornea. Thus, additional therapeutic agents are needed to enhance the antiangiogenic arsenal. Our group previously demonstrated epithelial membrane protein-2 (EMP2) involvement in pathologic angiogenesis in multiple cancer models including breast cancer and glioblastoma. In this paper, we investigate the efficacy of anti-EMP2 immunotherapy in the prevention of corneal neovascularization.

Methods

An in vivo murine cornea alkali burn model was used to study pathologic neovascularization. A unilateral corneal burn was induced using NaOH, and subconjunctival injection of either anti-EMP2 antibody, control antibody, or sterile saline was performed after corneal burn. Neovascularization was clinically scored at 7 days postalkali burn, and eyes were enucleated for histologic analysis and immunostaining including VEGF, CD31, and CD34 expression.

Results

Anti-EMP2 antibody, compared to control antibody or vehicle, significantly reduced neovascularization as measured by clinical score and central cornea thickness, as well as by histologic reduction of neovascularization, decreased CD34 staining, and decreased CD31 staining. Incubation of corneal limbal cells in vitro with anti-EMP2 blocking antibody significantly decreased EMP2 expression, VEGF expression and secretion, and cell migration.

Conclusions

This work demonstrates the effectiveness of EMP2 as a novel target in pathologic corneal neovascularization in an animal model and supports additional investigation into EMP2 antibody blockade as a potential new therapeutic option.

Immunotherapy beyond progression in advanced renal cell carcinoma: a case report and review of the literature

Immunotherapy is associated with different response patterns compared with chemotherapy and targeted therapy, including delayed response and stabilization after progression (pseudoprogression). According to new immuno-based response criteria, immunotherapy can be continued after radiological progression when a clinical benefit is observed. We report a case of an advanced renal cell carcinoma patient treated with nivolumab, who developed clinical benefit and delayed radiological response after initial progression. We performed a review of the literature on immunotherapy beyond progression in advanced solid tumors. 12 clinical trials were identified and showed that selected patients have subsequent response and survival benefit receiving immunotherapy beyond progression. Future studies are needed to optimize timing and duration of immunotherapy and to define patient selection criteria for treatment beyond progression.

Hemorrhage of MRI and Immunohistochemical Panels Distinguish Secretory Carcinoma From Acinic Cell Carcinoma

OBJECTIVES

Secretory carcinoma (SC, mammary analogue secretory carcinoma) is a salivary gland tumor with ETV6-NTRK3 gene fusion, and its differential diagnosis includes acinic cell carcinoma (ACC). As hemorrhage is often seen in SC, we hypothesized that magnetic resonance imaging (MRI) and immunohistochemical analyses could distinguish SC from ACC.

STUDY DESIGN

Retrospective study.

METHODS

We used ETV6-NTRK3 gene fusion analyses to reclassify 19 parotid gland tumors that had previously been diagnosed as SC or ACC, and then investigated hemorrhage in both hematoxylin-eosin (H&E)-stained sections and MRIs, and immunohistochemical expression of S-100, mammaglobin, DOG1, and α-amylase.

RESULTS

The 19 tumors were genetically reclassified into 11 (58%) SC and 8 (42%) ACC. Combined S-100 and mammaglobin were specific for SC; whereas DOG1 was specific for ACC, and α-amylase was expressed only in 4 ACC cases (50%). H&E staining showed hemorrhage with hemosiderin deposition in all SC cases, and T2-weighted MRI showed hypointense areas in all investigated SC cases, but not in ACC.

CONCLUSION

Hemorrhage with hemosiderin deposition is frequently present in SC, and hemorrhage findings in MRI and an immunohistochemical panels for S-100, mammaglobin and DOG1 can distinguish SC from ACC.

LEVEL OF EVIDENCE

3b.