Patients with muscle-invasive urothelial carcinoma achieving pathological complete response (pCR) upon neoadjuvant chemotherapy (NAC) have improved prognosis. Molecular subtypes of bladder cancer ...differ markedly regarding sensitivity to cisplatin-based chemotherapy and harbor FGFR treatment targets to various content. The objective of the present study was to evaluate whether preoperative assessment of molecular subtype as well as FGFR target gene expression is predictive for therapeutic outcome—rate of ypT0 status—to justify subsequent prospective validation within the “BladderBRIDGister”. Formalin-fixed paraffin-embedded (FFPE) tissue specimens from transurethral bladder tumor resections (TUR) prior to neoadjuvant chemotherapy and corresponding radical cystectomy samples after chemotherapy of 36 patients were retrospectively collected. RNA from FFPE tissues were extracted by commercial kits, Relative gene expression of subtyping markers (e.g., KRT5, KRT20) and target genes (FGFR1, FGFR3) was analyzed by standardized RT-qPCR systems (STRATIFYER Molecular Pathology GmbH, Cologne). Spearman correlation, Kruskal−Wallis, Mann−Whitney and sensitivity/specificity tests were performed by JMP 9.0.0 (SAS software). The neoadjuvant cohort consisted of 36 patients (median age: 69, male 83% vs. female 17%) with 92% of patients being node-negative during radical cystectomy after 1 to 4 cycles of NAC. When comparing pretreatment with post-treatment samples, the median expression of KRT20 dropped most significantly from DCT 37.38 to 30.65, which compares with a 128-fold decrease. The reduction in gene expression was modest for other luminal marker genes (GATA3 6.8-fold, ERBB2 6.3-fold). In contrast, FGFR1 mRNA expression increased from 33.28 to 35.88 (~6.8-fold increase). Spearman correlation revealed positive association of pretreatment KRT20 mRNA levels with achieving pCR (r = 0.3072: p = 0.0684), whereas pretreatment FGFR1 mRNA was associated with resistance to chemotherapy (r = −0.6418: p < 0.0001). Hierarchical clustering identified luminal tumors of high KRT20 mRNA expression being associated with high pCR rate (10/16; 63%), while the double-negative subgroup with high FGFR1 expression did not respond with pCR (0/9; 0%). Molecular subtyping distinguishes patients with high probability of response from tumors as resistant to neoadjuvant chemotherapy. Targeting FGFR1 in less-differentiated bladder cancer subgroups may sensitize tumors for adopted treatments or subsequent chemotherapy.
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Background: Patients with muscle invasive urothelial carcinoma achieving pathological complete response upon neoadjuvant chemotherapy (NACT) have improved prognosis. Previously we did show ...that luminal tumors respond better to NACT, while FGFR1 expression is associated with NACT resistance (Ecke et al. 2022). Interestingly the expression of the radioligand targets CXCR4 and FAP is found in chemoresistant, stroma-associated tumors. The objective of this study was to prospectively validate the predictive value of molecular target typing from TUR biopsy samples and compare PET CT imaging by FDG and FAP radioligand imaging in selected patients after two cycles of NACT to justify subsequent adaptive trial concepts within the "Bladder BRIDGister." Methods: Formalin fixed paraffin embedded tissues (FFPE) from transurethral resections (TUR) before chemotherapy and cystectomy samples after NACT of 36 patients were retrospectively collected and 650 TURB samples were prospectively collected as part of the Bladder BRIDGister. RNA from FFPE tissues were extracted by commercial kits, relative gene expression of subtyping markers (KRT5, KRT20, FGFR1) and radioligand target genes (CXCR4, FAP) were analyzed by standardized RT-qPCR systems (STRATIFYER Molecular Pathology GmbH, Cologne). PET CT Imaging by FDG and FAP was performed after two cycles cisplatinum based NACT. Results: The neoadjuvant cohort consisted of 36 patients (median age 69, male 83%, female 17%) with 92% of patients being node negative. Hierarchical clustering revealed CXCR4 and FAP to be elevated in stromal rich, KRT5 & KRT20 negative tumors not responding to NACT. Elevated FAP mRNA expression was sig. associated with resistance to NACT (chi
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4.314 p=0,0378). Combining elevated FAP and CXCR4 mRNA expression did identify 1/3 of the patients to be at high risk of NACT resistance (90%). Exemplarily one pT3 G3 patient was selected for PET CT imaging after two cycles that was predicted to be unresponsive to NACT by molecular subtyping. FDG PET CT revealed a hepatic metastatic lesion. In contrast FAP PET CT indicated multiple hepatic and a pancreatic metastatic lesion indicating tumor progression under NACT. Therapy was switched to MVAC with persistent non response. Then pembrolizumab monotherapy was administered due to PD-L1 positivity of the initial TURB (10% TPS /CPC 15). However there still was fulminant progression of the liver metastasis so that ICI therapy had to be stopped. Conclusions: Expression of the radioligand targets CXCR4 and FAP has been shown to be associated with aggressive stromal associated tumors and being resistant to NACT. This could be validated by selecting patients after two cycles of NACT for PET/CT imaging. Stratified FAP PET/CT turned out to be more sensitive than conventional FDG PET CT and may enable future theranostic treatment combinations in patients unresponsive to standard chemo- or immunotherapies.
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Background: Patients with muscle invasive urothelial carcinoma achieving pathological complete response (pCR) upon neoadjuvant chemotherapy (NACT) have improved prognosis. Molecular subtypes of ...bladder cancer differ markedly with regard to sensitivity to cisplatinum based chemotherapy. Previously we did show that luminal tumors respond better to NACT, while FGFR1 expression is associated with chemo resistance (Ecke et al. 2022). The objective of this study was to determine which patients may benefit from Antibody Drug Conjugate (ADC) treatment in addition to NACT to justify subsequent prospective analysis within the "Bladder BRIDGister". Methods: Formalin fixed paraffin embedded (FFPE) tissues from transurethral resections (TUR) before chemotherapy and cystectomy samples after NACT of 36 patients were retrospectively collected. RNA from FFPE tissues were extracted by commercial kits, relative gene expression of subtyping markers (KRT5, KRT20, FGFR1) and radioligand target genes (NECTIN4, TROP2) were analyzed by standardized RT-qPCR systems (STRATIFYER Molecular Pathology GmbH, Cologne). Spearman correlation, hierarchical clustering, Kruskal-Wallis, chi square and contingency tests were done by JMP 9.0.0 (SAS software). Results: The neoadjuvant cohort consisted of 36 patients (median age: 69, male 83% vs. female 17%) with 92% of patients being pathohistologically node negative. When comparing pretreatment with post treatment samples the median expression of KRT20 dropped 128fold, while FGFR1 expression increased 6.8 fold. Interestingly, TROP2 and NECTIN4 mRNA expression also dropped significantly upon NACT by 5.7 fold and 7.1 fold, respectively. TROP2 and NECTIN4 were positively associated with the response marker KRT20 in therapy naïve TUR biopsies (r=0.5562 p=0.0004; r=0.5833 p=0.0002), but negatively associated with the resistance marker FGFR1 (r=-0.2903 p=0,0858; r=-0.3396 p=0,0427). However, TROP2 and NECTIN4 were not associated with pCR in spearman analysis with minor trend for TROP2 (r=0,2139 p=0,2103). Cluster analysis revealed a subgroup of KRT20 positive and FGFR1 negative tumors expression TROP2 and NECTIN4, which achieved 80% pCR. In addition elevated TROP2 and NECTIN4 expression was found in KRT20 positive tumors coexpressing FGFR1 and being resistant to NACT. Conclusions: Expression of the ADC targets TROP2 and NECTIN4 is associated with KRT20 positive, luminal tumors being highly sensitive to neoadjuvant chemotherapy alone. KRT5 positive, basal tumors do exhibit only very low expression of TROP2 and NECTIN4 mRNA. In view of toxicities the addition of TROP2 and NECTIN4 treatment to NACT might be considered only in luminal tumors exhibiting elevated FGFR1 expression as resistance mechanism and therefore do not respond to NACT.
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Background: Patients with muscle invasive urothelial carcinoma achieving pathological complete response (pCR) upon neoadjuvant chemotherapy (NACT) have improved prognosis. Molecular subtypes of ...bladder cancer differ markedly with regard to sensitivity to cisplatinum based chemotherapy and harbour FGFR treatment targets to various content. Previously we did show that lumina tumors respond better to NACT, while FGFR1 expression is associated with chemo resistance (Ecke et al. 2022). The objective of this study was to determine wether radioligand therapy may be an appropriate option in chemoresistent tumors to justify subsequent prospective validation within the "Bladder BRIDGister". Methods: Formalin fixed paraffin embedded (FFPE) tissues from transurethral resections (TUR) before chemotherapy and cystectomy samples after NACT of 36 patients were retrospectively collected. RNA from FFPE tissues were extracted by commercial kits, relative gene expression of subtyping markers (KRT5, KRT20, FGFR1) and radioligand target genes (CXCR4, FAP) were analyzed by standardized RT-qPCR systems (STRATIFYER Molecular Pathology GmbH, Cologne). Spearman correlation, hierarchical clustering, Kruskal-Wallis, chi square and contingency tests were done by JMP 9.0.0 (SAS software). Results: The neoadjuvant cohort consisted of 36 patients (median age: 69, male 83% vs. female 17%) with 92% of patients being histopathologically node negative. When comparing pretreatment with post treatment samples the median expression of KRT20 dropped 128fold, while FGFR1, CXCR4 and FAP mRNA expression increased 6,8fold, 1,9 fold and 2,9 fold, respectively. FAP was positively associated with KRT5, FGFR1 and CXCR4 in treatment naïve TUR biopsies (r=0.4051 p=0.0141, r=0.6458 p<0.0001 and r=0.7586 p<0.0001, respectively), but negatively associated with KRT20 (r=-0.3879 p=0.0194). As previously described, FGFR1 was negatively associated with pCR (r=-0.6418 p<0.0001). Similarly, CXCR4 and FAP trended to be negatively associated with pCR (r=-0.3181 p=0.0586; r=-0.3072 p=0.0684). Hierarchical clustering revealed that CXCR4 and FAP are elevated in stromal rich, KRT5 & KRT20 negative tumors not responding to NACT. Elevated FAP above median mRNA expression was significantly associated with resistance to NACT (chi
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4.314 p=0,0378). Combining elevated FAP and CXCR4 mRNA expression did identify 28% of the patients to be at high risk of NACT resistance (90%). Conclusions: Expression of the radioligand targets CXCR4 and FAP are associated with basal/stromal enriched tumors and resistance to NACT. Theranostic targeting of CXCR4 and FAP before NACT might increase response towards NACT in this poor prognosis group.
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Background: Patients with muscle invasive urothelial carcinoma achieving pathological complete response (pCR) upon neoadjuvant chemotherapy (NACT) have improved prognosis. Previously we did show ...that luminal tumors respond better to NACT (Ecke et al 2022), while the radioligand targets CXCR4 and FAP are found in chemoresistant, stroma-associated tumors. The objective of this study was to exploit the expression of CXCR4 & FAP for theranostic imaging & treatment in selected patients by radioligand instillation into the bladder to justify subsequent adopted clinical trials within the Bladder BRIDGister framework. Methods: FFPE tumor tissues from 511 TURB samples were prospectively collected as part of the Bladder BRIDGister. RNA was extracted by commercial kits, relative gene expression of subtyping markers and radioligand target genes were analyzed by RT-qPCR. Hierarchical clustering, Kruskal-Wallis and contingency tests were done by JMP 9.0.0 (SAS software). PET/CT Imaging by CXCR4 and/or FAP instillation was performed in selected patients followed by systemic radioligand application after completion of cisplatinum based NACT to enable improved staging. Results: The prospective molecular registry cohort consisted of 511 bladder cancer patients included into the Bladder BRIDGister (median age: 75, male 74% vs. female 26%) with 5% Tis, 54% Ta, 16% T1 and 15% T2 stage and concomitant CIS being in 7%. CXCR4 expression was negatively associated with ERBB2 & FGFR3 mRNA (r=-0,3021 and r=-0,3326, p<0,0001). Inverse relation of FAP expression with ERBB2 & FGFR3 was even more pronounced (r=-0,4883 and r=-0,5177, p<0,0001). Clustering validated that CXCR4 and FAP are elevated in non-luminal tumors not responding to NACT. Exemplarily one stromal rich pT2 G3 MIBC patient with elevated FAP expression, who was predicted to be unresponsive to NACT, was selected for FDG and FAP PET/CT imaging after two cycles of NACT. Indeed metastatic lesion were detected in the liver and pancreatic tissue. FAP imaging revealed to be more sensitive than conventional FDG imaging. In a next step
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Ga-CXCR4 was instilled into the bladder of a patient with NACT-resistant MIBC rejecting cystectomy to establish a non-systemic approach for radioligand therapy. Theranostic instillation imaging revealed strong uptake into the invading MIBC and subsequent instillation therapy with
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Lu-FAP led to partial remission and increased immune cell infiltration indicating initial effectivity. Conclusions: Expression of the radioligand targets CXCR4 and FAP are associated with aggressive stromal and basal like tumors being resistant to NACT. This could be validated by selecting patients for FAP & CXCR4 PET/CT imaging. Instillation of radioligands into the bladder revealed to be safe with first signs of effectivity justifying clinical approaches as part of phase 1 / 2 clinical trials.
The humoral immune response to severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) vaccination in patients with chronic inflammatory disease (CID) declines more rapidly with tumor necrosis ...factor‐α (TNF‐α) inhibition. Furthermore, the efficacy of current vaccines against Omicron variants of concern (VOC) including BA.2 is limited. Alterations within immune cell populations, changes in IgG affinity, and the ability to neutralize a pre‐VOC strain and the BA.2 virus were investigated in these at‐risk patients. Serum levels of anti‐SARS‐CoV‐2 IgG, IgG avidity, and neutralizing antibodies (NA) were determined in anti‐TNF‐α patients (n = 10) and controls (n = 24 healthy individuals; n = 12 patients under other disease‐modifying antirheumatic drugs, oDMARD) before and after the second and third vaccination by ELISA, immunoblot and live virus neutralization assay. SARS‐CoV‐2‐specific B‐ and T cell subsets were analysed by multicolor flow cytometry. Six months after the second vaccination, anti‐SARS‐CoV‐2 IgG levels, IgG avidity and anti‐pre‐VOC NA titres were significantly reduced in anti‐TNF‐α recipients compared to controls (healthy individuals: avidity: p ≤ 0.0001; NA: p = 0.0347; oDMARDs: avidity: p = 0.0012; NA: p = 0.0293). The number of plasma cells was increased in anti‐TNF‐α patients (Healthy individuals: p = 0.0344; oDMARDs: p = 0.0254), while the absolute number of SARS‐CoV‐2‐specific plasma cells 7 days after 2nd vaccination were comparable. Even after a third vaccination, these patients had lower anti‐BA.2 NA titres compared to both other groups. We show a reduced SARS‐CoV‐2 neutralizing capacity in patients under TNF‐α blockade. In this cohort, the plasma cell response appears to be less specific and shows stronger bystander activation. While these effects were observable after the first two vaccinations and with older VOC, the differences in responses to BA.2 were enhanced.