Cutibacterium acnes-derived extracellular vesicles promote tumor growth in renal cell carcinoma.

Bacterial flora are present in various parts of the human body, including the intestine, and are thought to be involved in the etiology of various diseases such as multiple sclerosis, intestinal diseases, cancer, and uterine diseases. In recent years, the presence of bacterial 16S rRNA genes has been revealed in blood, which was previously thought to be a sterile environment, and characteristic blood microbiomes have been detected in various diseases. However, the mechanism and the origin of the bacterial information are unknown. In this study, we performed 16S rRNA metagenomic analysis of bacterial DNA in serum extracellular vesicles from five healthy donors and seven patients with renal cell carcinoma and detected Cutibacterium acnes DNA as a characteristic bacterial DNA in the serum extracellular vesicles of patients with renal cell carcinoma. In addition, C. acnes DNA was significantly reduced in postoperative serum extracellular vesicles from patients with renal cell carcinoma compared with that in preoperative serum extracellular vesicles from these patients and was also detected in tumor tissue and extracellular vesicles from tumor tissue-associated microbiota, suggesting an association between C. acnes extracellular vesicles and renal cell carcinoma. C. acnes extracellular vesicles were taken up by renal carcinoma cells to enhance their proliferative potential. C. acnes extracellular vesicles also exhibited tumor-promoting activity in a mouse model of renal cancer allografts with enhanced angiogenesis. These results suggest that extracellular vesicles released by C. acnes localized in renal cell carcinoma tissues act in a tumor-promoting manner.

Bacteria-derived DNA in serum extracellular vesicles are biomarkers for renal cell carcinoma.

This is the first study to determine the clinical importance of circulating bacterial DNA in patients with renal cell carcinoma (RCC). We performed 16S rRNA metagenomic analysis of serum extracellular vesicles (EVs) from 88 patients with RCC and 10 healthy donors and identified three abundant bacterial DNA: Bacteroidia, TM7-1, and Sphingomonadales. Combining characteristic bacterial DNA information (three bacteria-derived DNA), a BTS index was created to diagnose patients with RCC. The BTS index showed high sensitivity not only in the discovery cohort, but also in the validation cohort, suggesting that it was useful as a screening test. Furthermore, in nivolumab treatment of RCC, patients with higher levels of Bacteroidia DNA in serum EVs had significantly poorer progression-free and overall survival than did those with lower levels. This study showed that circulating Bacteria-derived DNA could be used as a biomarker for RCC.

ALKBH4 is a novel enzyme that promotes translation through modified uridine regulation.

Epitranscriptomics studies the mechanisms of acquired RNA modifications. The epitranscriptome is dynamically regulated by specific enzymatic reactions, and the proper execution of these enzymatic RNA modifications regulates a variety of physiological RNA functions. However, the lack of experimental tools, such as antibodies for RNA modification, limits the development of epitranscriptomic research. Furthermore, the regulatory enzymes of many RNA modifications have not yet been identified. Herein, we aimed to identify new molecular mechanisms involved in RNA modification by focusing on the AlkB homolog (ALKBH) family molecules, a family of RNA demethylases. We demonstrated that ALKBH4 interacts with small RNA, regulating the formation and metabolism of the (R)-5-carboxyhydroxymethyl uridine methyl ester. We also found that the reaction of ALKBH4 with small RNA enhances protein translation efficiency in an in vitro assay system. These findings indicate that ALKBH4 is involved in the regulation of uridine modification and expand on the role of tRNA-mediated translation control through ALKBH4.

Hypoxia regulates tumour characteristic RNA modifications in ovarian cancers.

Analysis of ovarian cancer tissue and normal ovarian tissue revealed 31 RNA modifications with significant differences observed in cancer tissue compared with normal tissue. Moreover, we found Im and chm5U as characteristic RNA modifications in advanced and platinum-resistant ovarian cancers, respectively. Considering that these differences in RNA modifications may be due to the intra-tumour microenvironment, we xenografted the ovarian cancer cell line RMG-1 to create RMG-1 tumours and compared them with original RMG-1 cells. As a result, 14 of the 31 RNA modifications showed marked variations during tumorigenesis. Eight RNA modifications (m2,2G, t6A, m7G, m5U, m1G, i6A, m6t6A and m1A), which were upregulated in ovarian cancer tissues and in RMG-1-xenografted tumour, were also upregulated under hypoxic conditions. RNAseq analysis, using the matched RNA samples analysed for RNA modifications, showed that 2137 genes were highly expressed in ovarian cancer tissues compared with those in normal ovarian tissues. Of these, 134 genes, which were enriched in a gene set belonging to the hypoxia signalling pathway, were positively correlated with the above eight RNA modifications. These results suggest that the tumour microenvironment, including hypoxia, is important for cancer characteristic RNA modifications.

Circulating extracellular vesicles carrying Firmicutes reflective of the local immune status may predict clinical response to pembrolizumab in urothelial carcinoma patients.

Bacterial flora has clinical significance for the host. The metabolic environment created by this flora influences immunotherapy in urothelial carcinoma. However, there are no reports on the clinical significance of bacterial flora in the host bloodstream. We aimed to clarify the correlation between extracellular vesicle (EV)-derived blood microflora information and tumor immunological status in urothelial carcinoma (UC) patients. Serum samples were collected from 20 healthy donors, 50 patients with localized UC, and 31 patients with metastatic UC (mUC) who had undergone pembrolizumab treatment. Bacterial DNA in EVs was extracted from each sample. Metagenomic sequencing was performed after amplification of the V1-V2 region of the bacterial 16S rRNA gene. Using the matched tumor tissue and serum samples, we revealed that the smaller amount of peripheral EVs carrying Firmicutes DNA was significantly correlated with the higher number of infiltrating T cells within tumor tissues (CD3; p = 0.015, CD4; p = 0.039, CD8; p = 0.0084) and the higher expression of activation markers on their surface (ICOS on both CD4; p = 0.0013 and CD8 T cells; p = 0.016 and 4-1BB on CD4 T cells; p = 0.016). In terms of circulating metabolic information, L-Ser and L-Pro levels, which play important roles in T cell expansion and proliferation, were significantly higher in the Firmicutes-low group (p = 0.010). All of the patients with higher Firmicutes abundance had disease progression without any clinical response (p = 0.026) and significantly inferior prognosis for pembrolizumab therapy (p = 0.035). This is the first study on the importance of peripheral bacterial EVs in cancer patients treated with cancer immunotherapy.

Azurocidin is loaded into small extracellular vesicles via its N-linked glycosylation and promotes intravasation of renal cell carcinoma cells.

Azurocidin (AZU1) is an antimicrobial protein secreted by neutrophils that acts as a chemoattractant for monocytes and macrophages and a permeabilizer of vascular endothelial cells. We previously identified AZU1 to be specifically present in extracellular vesicles (EVs) obtained from renal cell carcinoma (RCC) tissues. Here, we examined the relationship between N-linked glycosylation and AZU1 loading into small EVs (SEVs). Inhibition of N-linked glycosylation by introducing mutations in three glycosylation sites inhibited AZU1 loading into SEVs. Furthermore, SEVs released from AZU1-wild-type cells increased the Ca2+ concentration in endothelial cells and the endothelial permeability, whereas SEVs released from AZU1-mutant cells had no significant effect. Anti-AZU1 antibodies diminished the effect of SEVs on endothelial cell sheets. Collectively, we found that N-linked glycosylation of AZU1 directs its loading into SEVs, thereby enabling AZU1-positive SEVs to function as potent permeabilizers of endothelial cells and leading to enhanced transendothelial migration of RCC cells.

Gut Microbiota-Derived Short-Chain Fatty Acids Promote Prostate Cancer Growth via IGF1 Signaling.

Excessive intake of animal fat and resultant obesity are major risk factors for prostate cancer. Because the composition of the gut microbiota is known to change with dietary composition and body type, we used prostate-specific Pten knockout mice as a prostate cancer model to investigate whether there is a gut microbiota-mediated connection between animal fat intake and prostate cancer. Oral administration of an antibiotic mixture (Abx) in prostate cancer-bearing mice fed a high-fat diet containing a large proportion of lard drastically altered the composition of the gut microbiota including Rikenellaceae and Clostridiales, inhibited prostate cancer cell proliferation, and reduced prostate Igf1 expression and circulating insulin-like growth factor-1 (IGF1) levels. In prostate cancer tissue, MAPK and PI3K activities, both downstream of the IGF1 receptor, were suppressed by Abx administration. IGF1 directly promoted the proliferation of prostate cancer cell lines DU145 and 22Rv1 in vitro. Abx administration also reduced fecal levels of short-chain fatty acids (SCFA) produced by intestinal bacteria. Supplementation with SCFAs promoted tumor growth by increasing IGF1 levels. In humans, IGF1 was found to be highly expressed in prostate cancer tissue from obese patients. In conclusion, IGF1 production stimulated by SCFAs from gut microbes influences the growth of prostate cancer via activating local prostate MAPK and PI3K signaling, indicating the existence of a gut microbiota-IGF1-prostate axis. Disrupting this axis by modulating the gut microbiota may aid in prostate cancer prevention and treatment. SIGNIFICANCE: These results suggest that intestinal bacteria, acting through short-chain fatty acids, regulate systemic and local prostate IGF1 in the host, which can promote proliferation of prostate cancer cells.

MiR-30b-3p and miR-126-3p of urinary extracellular vesicles could be new biomarkers for prostate cancer.

BACKGROUND: Extracellular vesicles (EVs) including exosomes are present in blood, urine, and saliva and contain proteins, microRNAs, and messenger RNAs. We investigated microRNAs in urinary EVs to discover new biomarkers of prostate cancer (PCa). METHODS: We isolated EVs from urine obtained following digital rectal examination (DRE) of 14 men with elevated levels of serum prostate-specific antigen (PSA) [negative biopsy (n=4) and PCa with Gleason scores of 6 (n=3), 7 (n=3), and 8-9 (n=4)]. MicroRNAs extracted from EVs were analyzed by microRNA microarray. RESULTS: MicroRNAs miR-30b-3p and miR-126-3p were identified as being overexpressed in urinary EVs of the PCa patients versus the biopsy-negative men, but no microRNAs were associated with the Gleason score. In the independent cohort as well, these two microRNAs were overexpressed in urinary EVs from the PCa patients versus the negative-biopsy men. Logistic regression analysis adjusted by age and PSA showed that these two microRNAs were significantly associated with the prediction of PCa in biopsy specimens. Sensitivity and specificity of miR-30b-3p and miR-126-3p for the prediction of PCa were 46.4% and 88.0% and 60.7% and 80.0%, respectively, which were better than those of serum PSA (53.5% and 64.0%, respectively). CONCLUSIONS: MiR-30b-3p and miR-126-3p in urinary EVs could be potential biomarkers of PCa.

Pharmacological Inhibition of miR-130 Family Suppresses Bladder Tumor Growth by Targeting Various Oncogenic Pathways via PTPN1.

Previously, we have revealed that the miR-130 family (miR-130b, miR-301a, and miR-301b) functions as an oncomiR in bladder cancer. The pharmacological inhibition of the miR-130 family molecules by the seed-targeting strategy with an 8-mer tiny locked nucleic acid (LNA) inhibits the growth, migration, and invasion of bladder cancer cells by repressing stress fiber formation. Here, we searched for a functionally advanced target sequence with LNA for the miR-130 family with low cytotoxicity and found LNA #9 (A(L)^i^i^A(L)^T(L)^T(L)^G(L)^5(L)^A(L)^5(L)^T(L)^G) as a candidate LNA. LNA #9 inhibited cell growth in vitro and in an in vivo orthotopic bladder cancer model. Proteome-wide tyrosine phosphorylation analysis suggested that the miR-130 family upregulates a wide range of receptor tyrosine kinases (RTKs) signaling via the expression of phosphorylated Src (pSrcTyr416). SILAC-based proteome analysis and a luciferase assay identified protein tyrosine phosphatase non-receptor type 1 (PTPN1), which is implicated as a negative regulator of multiple signaling pathways downstream of RTKs as a target gene of the miR-130 family. The miR-130-targeted LNA increased and decreased PTPN1 and pSrcTyr416 expressions, respectively. PTPN1 knockdown led to increased tumor properties (cell growth, invasion, and migration) and increased pSrcTyr416 expression in bladder cancer cells, suggesting that the miR-130 family upregulates multiple RTK signaling by targeting PTPN1 and subsequent Src activation in bladder cancer. Thus, our newly designed miR-130 family targeting LNA could be a promising nucleic acid therapeutic agent for bladder cancer.

ALKBH4 promotes tumourigenesis with a poor prognosis in non-small-cell lung cancer.

The human AlkB homolog family (ALKBH) of proteins play a critical role in some types of cancer. However, the expression and function of the lysine demethylase ALKBH4 in cancer are poorly understood. Here, we examined the expression and function of ALKBH4 in non-small-cell lung cancer (NSCLC) and found that ALKBH4 was highly expressed in NSCLC, as compared to that in adjacent normal lung tissues. ALKBH4 knockdown significantly induced the downregulation of NSCLC cell proliferation via cell cycle arrest at the G1 phase of in vivo tumour growth. ALKBH4 knockdown downregulated E2F transcription factor 1 (E2F1) and its target gene expression in NSCLC cells. ALKBH4 and E2F1 expression was significantly correlated in NSCLC clinical specimens. Moreover, patients with high ALKBH4 expression showed a poor prognosis, suggesting that ALKBH4 plays a pivotal tumour-promoting role in NSCLC.

Proteomic analysis of urinary and tissue-exudative extracellular vesicles to discover novel bladder cancer biomarkers.

Proteomic analysis of urinary extracellular vesicles (EVs) is a powerful approach to discover potential bladder cancer (BCa) biomarkers, however urine contains numerous EVs derived from the kidney and normal urothelial epithelium, which can obfuscate information related to BCa cell-derived EVs. In this study, we combined proteomic analysis of urinary EVs and tissue-exudative EVs (Te-EVs), which were isolated from culture medium of freshly resected viable BCa tissues. Urinary EVs were isolated from urine samples of 11 individuals (7 BCa patients and 4 healthy individuals), and Te-EVs were isolated from 7 BCa tissues. We performed tandem mass tag (TMT)-labeling liquid chromatography (LC-MS/MS) analysis for both urinary EVs and Te-EVs and identified 1960 proteins in urinary EVs and 1538 proteins in Te-EVs. Most of the proteins identified in Te-EVs were also present in urinary EVs (82.4%), with 55 of these proteins showing upregulated levels in the urine of BCa patients (fold change > 2.0; P < .1). Among them, we selected 22 membrane proteins as BCa biomarker candidates for validation using selected reaction monitoring/multiple reaction monitoring (SRM/MRM) analysis on urine samples from 70 individuals (40 BCa patients and 30 healthy individuals). Six urinary EV proteins (heat-shock protein 90, syndecan-1, myristoylated alanine-rich C-kinase substrate (MARCKS), MARCKS-related protein, tight junction protein ZO-2, and complement decay-accelerating factor) were quantified using SRM/MRM analysis and validated as significantly upregulated in BCa patients (P < .05). In conclusion, the novel strategy that combined proteomic analysis of urinary EVs and Te-EVs enabled selective detection of urinary BCa biomarkers.

Development of a highly sensitive method for the quantitative analysis of modified nucleosides using UHPLC-UniSpray-MS/MS.

There are more than 150 types of naturally occurring modified nucleosides, which are believed to be involved in various biological processes. Recently, an ultrahigh performance liquid chromatography-electrospray ionization-tandem mass spectrometry (UHPLC-ESI-MS/MS) technique has been developed to measure low levels of modified nucleosides. A comprehensive analysis of modified nucleosides will lead to a better understanding of intracellular ribonucleic acid modification, but this analysis requires high-sensitivity measurements. In this perspective, we established a highly sensitive and quantitative method using the newly developed ion source, UniSpray. A mass spectrometer was used with a UniSpray source in positive ion mode. Our UHPLC-UniSpray-MS/MS methodology separated and detected the four major nucleosides, 42 modified nucleosides, and dG15N5 (internal standard) in 15 min. The UniSpray method provided good correlation coefficients (>0.99) for all analyzed nucleosides, and a wide range of linearity for 35 of the 46 nucleosides. Additionally, the accuracy and precision values satisfied the criteria of <15% for higher concentrations and <20% for the lowest concentrations of all nucleosides. We also investigated whether this method could measure nucleosides in biological samples using mouse tissues and non-small cell lung cancer clinical specimens. We were able to detect 43 and 31 different modified nucleosides from mouse and clinical tissues, respectively. We also found significant differences in the levels of N6-methyl-N6-threonylcarbamoyladenosine (m6t6A), 1-methylinosine (m1I), 2'-O-methylcytidine (Cm), 5-carbamoylmethyluridine (ncm5U), 5-methoxycarbonylmethyl-2-thiouridine (mcm5S2U), and 5-methoxycarbonylmethyl-2'-O-methyluridine (mcm5Um) between cancerous and noncancerous tissues. In conclusion, we developed a highly sensitive methodology using UHPLC-UniSpray-MS/MS to simultaneously detect and quantify modified nucleosides, which can be used for analysis of biological samples.

Cancer type­SLCO1B3 promotes epithelial­mesenchymal transition resulting in the tumour progression of non­small cell lung cancer.

Non­small cell lung cancer (NSCLC) is one of the most common histologically defined subtypes of lung cancer. To identify a promising molecular target for NSCLC therapy, we performed gene expression analysis at the exon level using postoperative specimens of NSCLC patients. Exon array and real­time PCR analyses revealed that an alternative splicing variant of solute carrier organic anion transporter family member 1B3 (SLCO1B3) called cancer type­SLCO1B3 (Ct­SLCO1B3) was significantly upregulated in the NSCLC samples. SLCO1B3 expressed in the liver [liver type (Lt)­SLCO1B3] was found to be localised in the cell membrane, whereas Ct­SLCO1B3 was detected in the cytoplasm of NSCLC cells. RNAi­mediated knockdown of Ct­SLCO1B3 inhibited in vitro anchorage­independent cell growth, cell migration, and in vivo tumour growth of A549 cells. Overexpression of Ct­SLCO1B3 but not Lt­SLCO1B3 upregulated anchorage­independent cell growth and cell migration of NCI­H23 cells. Mechanistically, Ct­SLCO1B3 was found to regulate the expression of epithelial­mesenchymal transition (EMT)­related genes. The upregulation of E­cadherin was discovered to be especially pivotal to phenotypes of Ct­SLCO1B3­suppressed A549 cells. These findings suggest that Ct­SLCO1B3 functions as a tumour­promoting factor via regulating EMT­related factors in NSCLC.

MicroRNA-92b-3p is a prognostic oncomiR that targets TSC1 in clear cell renal cell carcinoma.

Although several studies have reported that microRNA (miR)-92b-3p is involved in various cellular processes related to carcinogenesis, its physiological role in clear cell renal cell carcinoma (ccRCC) remains unclear. To clarify the role of miR-92b-3p in ccRCC, we compared miR-92b-3p expression levels in ccRCC tissues and adjacent normal renal tissues. Significant upregulation of miR-92b-3p was observed in ccRCC tissues. Overexpression of miR-92b-3p using a miRNA mimic promoted proliferation, migration, and invasion activities of ACHN cells. Functional inhibition of miR-92b-3p by a hairpin miRNA inhibitor suppressed Caki-2 cell growth and invasion activities in vitro. Mechanistically, it was found that miR-92b-3p directly targeted the TSC1 gene, a known upstream regulator of mTOR. Overexpression of miR-92b-3p decreased the protein expression of TSC1 and enhanced the downstream phosphorylation of p70S6 kinase, suggesting that the mTOR signaling pathway was activated by miR-92b-3p in RCC cells. Importantly, a multivariate Cox proportion hazard model, based on TNM staging and high levels of miR-92b-3p, revealed that miR-92b-3p expression (high vs. low hazard ratio, 2.86; 95% confidence interval, 1.20-6.83; P = .018) was a significant prognostic factor for overall survival of ccRCC patients with surgical management. Taken together, miR-92b-3p was found to act as an oncomiR, promoting cell proliferation by downregulating TSC1 in ccRCC.

MicroRNA-130b functions as an oncomiRNA in non-small cell lung cancer by targeting tissue inhibitor of metalloproteinase-2.

Non-small cell lung cancer (NSCLC) is the most frequent cause of cancer-related death worldwide. Although many molecular-targeted drugs for NSCLC have been developed in recent years, the 5-year survival rate of patients with NSCLC remains low. Therefore, an improved understanding of the molecular mechanisms underlying the biology of NSCLC is essential for developing novel therapeutic strategies for the treatment of NSCLC. In this study, we examined the role of miR-130b in NSCLC. Our results showed that high expression of miR-130b in clinical specimens was significantly associated with poor overall survival in patients with NSCLC. Moreover, miR-130b expression was significantly increased in NSCLC clinical specimens from patients with vascular and lymphatic invasion. Consistent with this, overexpression of miR-130b promoted invasion and matrix metalloproteinase-2 (MMP-2) activity in A549 cells. Argonaute2 immunoprecipitation and gene array analysis identified tissue inhibitor of metalloproteinase-2 (TIMP-2) as a target of miR-130b. Invasion activity promoted by miR-130b was attenuated by TIMP-2 overexpression in A549 cells. Furthermore, TIMP-2 concentrations in serum were inversely correlated with relative miR-130b expression in tumor tissues from the same patients with NSCLC. Overall, miR-130b was found to act as an oncomiR, promoting metastasis by downregulating TIMP-2 and invasion activities in NSCLC cells.

Diagnostic potential of TERT promoter and FGFR3 mutations in urinary cell-free DNA in upper tract urothelial carcinoma.

Most upper tract urothelial carcinomas (UTUC) are muscle invasive at the time of diagnosis. Current standard methods for the diagnosis of UTUC are invasive. Urine cytology is the only non-invasive test for detecting UTUC, but its sensitivity is low. A novel non-invasive assay for UTUC detection would improve patient outcome. This study aimed to investigate the mutation of cell-free DNA (cfDNA) in urine supernatant to develop a reliable diagnostic biomarker for UTUC patients. We studied urinary cfDNA from 153 individuals, including 56 patients with localized UTUC, and carried out droplet digital PCR assay for TERT promoter and FGFR3 hotspot mutations. We could detect mutations of TERT C228T in 22/56 (39.3%), TERT C250T in 4/56 (7.1%), and FGFR3 S249C in 9/56 (16.1%) patients. FGFR3 mutation was detected only in ≤pT1 tumors (positive predictive value: 100.0%). In combination with cytology results, the sensitivity was 78.6%, and the specificity was 96.0%. Although these data need to be validated in a larger-scale cohort, mutation analysis of TERT promoter and FGFR3 in urinary cfDNA has the potential to be a non-invasive diagnostic marker and reliable factor for tumor staging.

Leukocyte­associated immunoglobulin­like receptor 1 promotes tumorigenesis in RCC.

Renal cell carcinoma (RCC) is the most common type of kidney cancer in adults, responsible for approximately 90­95% of cases. We previously reported a novel method that enables direct extraction of extracellular vesicles (EVs) from surgically resected viable tissues, yielding what we term tissue­exudative extracellular vesicles (Te­EVs). Quantitative LC/MS analysis identified 3,871 proteins in Te­EVs, among which leukocyte­associated immunoglobulin­like receptor 1 (LAIR1) was highly enriched in tumor Te­EVs. In the present study, we found that LAIR1 was significantly upregulated in clinical specimens of human RCC tumor tissues compared to that noted in adjacent non­cancerous renal tissues as determined by quantitative PCR analysis. LAIR1 overexpression resulted in accelerated cell proliferation and tumor growth in RCC cells. Moreover, knockdown of LAIR1 using siRNA significantly inhibited cell proliferation in RCC cells. Mechanistically, LAIR1 upregulated the phosphorylation status of Akt, which in turn increased cell proliferation in RCC cells. In clinical RCC specimens, RCC patients with high LAIR1 mRNA expression showed poor progression­free survival compared to those with low LAIR1 expression. These findings indicate that LAIR1 promotes tumorigenesis in RCC.

Clinical significance of the mutational landscape and fragmentation of circulating tumor DNA in renal cell carcinoma.

Reliable biomarkers for renal cell carcinoma (RCC) have yet to be determined. Circulating tumor DNA (ctDNA) is an emerging resource to detect and monitor molecular characteristics of various tumors. The present study aims to clarify the clinical utility of ctDNA for RCC. Fifty-three patients histologically diagnosed with clear cell RCC were enrolled. Targeted sequencing was carried out using plasma cell-free DNA (cfDNA) and tumor DNA. We applied droplet digital PCR (ddPCR) to validate detected mutations. cfDNA fragment size was also evaluated using a microfluidics-based platform and sequencing. Proportion of cfDNA fragments was defined as the ratio of small (50-166 bp) to large (167-250 bp) cfDNA fragments. Association of mutant allele frequency of ctDNA with clinical course was analyzed. Prognostic potential was evaluated using log-rank test. A total of 38 mutations across 16 (30%) patients were identified from cfDNA, including mutations in TP53 (n = 6) and VHL (n = 5), and median mutant allele frequency of ctDNA was 10%. We designed specific ddPCR probes for 11 mutations and detected the same mutations in both cfDNA and tumor DNA. Positive ctDNA was significantly associated with a higher proportion of cfDNA fragments (P = .033), indicating RCC patients with ctDNA had shorter fragment sizes of cfDNA. Interestingly, the changes of mutant allele frequency in ctDNA concurrently correlated with clinical course. Positive ctDNA and fragmentation of cfDNA were significantly associated with poor cancer-specific survival (P < .001, P = .011). In conclusion, our study shows the clinical utility of ctDNA status and cfDNA fragment size as biomarkers for prognosis and disease monitoring in RCC.

Phenotypic Analysis of Tumor Tissue-Infiltrating Lymphocytes in Tumor Microenvironment of Bladder Cancer and Upper Urinary Tract Carcinoma.

BACKGROUND: There are no previous reports directly evaluating immunologic conditions in tumor microenvironment including both bladder cancer (BCa) and upper urinary tract carcinoma (UTUC). In this study, we aimed to clarify the difference of immunity status and its clinical significance depending on the tumor site in urothelial carcinoma. PATIENTS AND METHODS: Tumor tissue-infiltrating lymphocytes were extracted from 70 urothelial cancer patients who underwent surgical resection (52 cases of BCa and 18 cases of UTUC). The immunologic classification was established by unsupervised clustering analysis according to the expression ratio of 9 extracellular surface markers measured by flow cytometry, and we examined the relationship between immunologic classification and clinical importance such as pathologic status and prognosis (progression-free survival and cancer-specific survival). RESULTS: The immunologic condition was classified into 2 groups. Group 1 (n = 41) comprised the CD4 T-cell-dominant group and group 2 (n = 29) the immunologically activated group. This immunologic classification was significantly correlated with tumor grade (P = .020) but not tumor location in multivariate analysis. In invasive BCa patients (n = 33), progression-free survival and cancer-specific survival of group 2 were significantly worse than those of group 1 (P = .021 and P = .022, respectively), while there was no significant difference between groups 1 and 2 in patients with invasive UTUC (n = 17). CONCLUSION: Although there was no difference in the local immunologic condition of urothelial carcinoma between BCa and UTUC, its significance as a prognostic predictor might vary depending on tumor site.

STAT3 expression is a prognostic marker in upper urinary tract urothelial carcinoma.

Signal transducer and activator of transcription 3 (STAT3) plays a prominent role in the growth and invasion of several types of solid tumors. In this study, to assess the expression status and prognostic significance of the STAT3 pathway in upper urinary tract urothelial carcinoma (UTUC), we immunohistochemically stained for STAT3 and STAT3 pathway proteins, sphingosine-1-phosphate receptor 1 (S1PR1) and interleukin-6 (IL-6), in a tissue microarray containing 99 UTUC specimens. There were no significant associations between STAT3, S1PR1, or IL-6 expression pattern and tumor grade or pT stage. However, the patients with high STAT3 tumor had a significantly higher risk of both disease progression (p = 0.009) and cancer-specific mortality (p = 0.009), but not with tumors expressing S1PR1 or IL-6. High STAT3 expression in the nucleus was also associated with a significantly higher risk of both disease progression (p = 0.003) and cancer-specific mortality (p = 0.034). Multivariate analysis revealed that high STAT3 expression in the nucleus was significantly associated with cancer-specific survival after adjustment for pathological stage, lymph node involvement, lymphovascular invasion, and tumor grade (HR = 2.136, 95% CI = 1.009-4.767, p = 0.047). Our findings indicated that STAT3 could be a cancer-promoting factor and potentially a significant prognostic factor in UTUC.