Due to a production error, there were some mistakes in the published version, which have been corrected and are described below.
The first sentence was rephrased for clarity. A correction has been made to the section Introduction:
“Urinary bladder cancer (UBC) was among the most prevalent cancers worldwide, ranking seventh by five-year prevalence in 2020, with more than 1.7 million people living within five years of diagnosis.”
A sentence was rephrased for clarify. A correction has been made to the section 3 LCT-mediated mechanisms of oncobiotics in UBC-oncotherapy, 3.1 Direct tumor destruction:
“Species such as Listeria monocytogenes have been associated with reactive oxygen species (ROS) production and modulation of host immune responses, mechanisms that may contribute to antitumor activity (27), while Escherichia coli secretes cytolysin A, leading to membrane disruption and caspase-dependent cell death (28).”
A correction has been made to Section 3.4 Oncolytic viruses (direct lysis and immune priming), Paragraph 2:
“Early preclinical work established the feasibility of transcriptionally targeted oncolytic adenoviruses for bladder cancer. In 2002, Zhang et al. developed CG8840 by placing adenovirus type 5 under the control of the human uroplakin II promoter, thereby restricting viral replication to urothelial carcinoma cells. CG8840 demonstrated selective replication in malignant urothelial cells and significantly inhibited tumor growth in human bladder cancer xenograft models after intravenous or intratumoral administration (55). Although CG8840 itself was an early experimental construct, it provided important proof-of-concept for the later development of clinically advanced bladder cancer–specific oncolytic adenoviruses such as cretostimogene grenadenorepvec (CG0070).”
Sievert, K.D., Amend, B., Nagele, U. et al. Economic aspects of bladder cancer: what are the benefits and costs?. World J Urol 27, 295–300 (2009). https://doi.org/10.1007/s00345-009-0395-z was not cited in the article. The citation has now been inserted in the section Introduction, Paragraph 1, after the sentence:
“UBC is recognized as the cancer entailing the highest lifetime treatment costs per patient.”
Lin NYT, Fukuoka S, Koyama S, et al. Microbiota-driven antitumour immunity mediated by dendritic cell migration. Nature. (2025) 644:1058–1068. doi: 10.1038/s41586-025-09249–8 was not cited in the article. The citation has now been inserted in the section 3.2.1 Innate-to-adaptive immune activation after the sentence:
“Beyond classical bacterial species, emerging LCTs such as Hominenteromicrobium mulieris and Enterococcus gallinarum demonstrated the ability to stimulate dendritic cells and enhance cytokine production, leading to amplified innate antitumor immunity and improved responsiveness to immunotherapies”
Miest T, Leibovich B, Bardot S, Young P, Boorjian S, Gonzalgo M, et al. 422 Safety and efficacy of neoadjuvant intravesical oncolytic MV-NIS in patients with urothelial carcinoma. J Immunother Cancer. (2021) 9. doi: 10.1136/jitc-2021-SITC2021.422
was not cited in the article. The citation has now been inserted in Section 3.4 Oncolytic viruses (direct lysis and immune priming), after the sentence:
“Beyond adenoviruses and VSV, other oncolytic viruses have demonstrated immunomodulatory potential. Intravesical administration of MV-NIS, an oncolytic measles virus encoding the sodium-iodide symporter, was evaluated in patients undergoing cystectomy and resulted in tumor downstaging and marked immune cell infiltration with minimal toxicity.”
Binhui Biopharmaceutical Co., Ltd. OH2 Oncolytic Viral Therapy in Non-Muscle-Invasive Bladder Cancer. ClinicalTrials.gov identifier: NCT05232136. Bethesda (MD): National Library of Medicine (US); updated August 12, 2024. Available from: https://clinicaltrials.gov/study/NCT05232136 was not cited in the article. The citation has now been inserted in 3.4 Oncolytic viruses (direct lysis and immune priming), after the sentence:
“OH2, a genetically engineered herpes simplex virus type 2 expressing GM-CSF, combines direct oncolysis with immune stimulation and is currently under clinical evaluation in patients with NMIBC unresponsive to first-line intravesical therapy.”
There was a mistake in Table 1 as published. In the “Developmental stage” column, the entry for CVA21 (CAVATAK) was erroneously given as “Phase I/II”. The correct developmental stage is “Phase I”. The corrected Table 1 appears below.
Table 1
| Therapeutic platform | Type of LCT | Mechanism of action | Route of administration | Immune effects | Developmental stage | Translational/clinical status |
|---|---|---|---|---|---|---|
| BCG (Bacillus Calmette–Guérin) | Live attenuated bacteria | Activation of innate and adaptive antitumor immunity | Intravesical | Strong activation of macrophages, NK cells, dendritic cells, and T cells | Clinically established | Current standard of care for high-risk NMIBC |
| CG0070 | Oncolytic adenovirus expressing GM-CSF | Selective replication in Rb-deficient tumor cells with GM-CSF-mediated immune activation | Intravesical | Promotes immunogenic cell death and local immune stimulation | Phase II/III | Promising efficacy in BCG-unresponsive NMIBC |
| CVA21 (CAVATAK) | Oncolytic coxsackievirus | Selective viral replication and tumor lysis via ICAM-1 targeting | Intravesical | Induces tumor inflammation and immune gene upregulation | Phase I | Early clinical proof-of-concept established |
| Nadofaragene firadenovec | Adenoviral gene therapy | Delivery of IFN-α2b gene to urothelial cells | Intravesical | Enhances interferon-mediated antitumor immunity | FDA-approved | Approved for BCG-unresponsive NMIBC |
| OH2 | Genetically modified HSV-2 | Direct oncolysis combined with GM-CSF-mediated immune activation | Intratumoral / intravesical | Enhances immune cell recruitment and activation | Phase I/II | Under clinical evaluation |
| MV-NIS | Oncolytic measles virus | Selective viral infection and tumor destruction | Intravesical / intravenous | Promotes immune infiltration and tumor inflammation | Early clinical development | Under clinical evaluation |
| Lactobacillus spp. (LGG, L. casei) | Probiotic bacteria | Immune modulation and enhancement of antitumor immune signaling | Oral and intravesical | Enhances macrophage and neutrophil recruitment | Preclinical and clinical adjunct studies | Potential adjunctive immunomodulatory strategy |
| Engineered Salmonella spp. | Genetically modified bacterial vector | Tumor-selective delivery of siRNA and immunomodulatory payloads | Intravesical / experimental systemic administration | Increases CD8+ T-cell infiltration and immune activation | Preclinical | Promising programmable delivery platform |
| Bifidobacterium infantis–HSV-TK system | Engineered probiotic suicide-gene therapy | HSV-TK/ganciclovir-mediated induction of tumor apoptosis | Experimental intravesical delivery | Indirect immune activation secondary to tumor apoptosis | Preclinical | Proof-of-concept demonstrated in animal models |
| IL-15–engineered Salmonella VNP20009 | Synthetic bacterial immunotherapy | Localized IL-15/IL-15Rα cytokine delivery | Intravesical | Strong activation of NK cells and CD8+ T cells | Preclinical | High translational potential for immune enhancement |
| MCNA (Mycobacterium phlei cell wall–nucleic acid complex) | Bacterial-derived immunotherapy | Immune stimulation and pro-apoptotic activity | Intravesical | Enhances local immune activation | Early clinical evaluation | Investigated in BCG-unresponsive NMIBC |
| Bacteriobots (engineered E. coli Nissle 1917) | Bioengineered bacterial microrobots | Targeted tumor localization and ROS-mediated tumor destruction | Experimental local delivery | Potential secondary immune activation | Early preclinical | Emerging next-generation precision platform |
Overview of living cancer therapeutics in urinary bladder cancer.
There was a mistake in Table 2 as published. In the “Treatment category” column, the following entries were erroneously given and have been corrected:
KD01 (NCT07359235): “Intravesical viral immunotherapy” has been corrected to “Recombinant/oncolytic adenoviral therapy”.
VT-101 (NCT06632964): “Viral immunotherapy” has been corrected to “Recombinant/oncolytic adenoviral therapy”.
ZH9 (NCT06181266): “Viral immunotherapy” has been corrected to “Salmonella enterica serovar Typhi–based bacterial immunotherapy”.
Table 2
| Clinical trial identifier | Therapeutic platform | Treatment category | Study status | Disease setting | Intervention / strategy | Main objective |
|---|---|---|---|---|---|---|
| NCT06668493 | Nadofaragene firadenovec | Recombinant adenoviral IFN-α gene therapy | Recruiting | Low-grade UTUC | Administration of nadofaragene firadenovec to the renal pelvis | Assessment of safety and efficacy in upper tract urothelial disease |
| NCT07332351 (TRIFECTA) | Nadofaragene firadenovec + gemcitabine/cisplatin + durvalumab | Combination gene-immunochemotherapy | Not yet recruiting | MIBC | Neoadjuvant intravesical nadofaragene firadenovec combined with systemic chemotherapy and immune checkpoint inhibition | Evaluation of bladder-preserving multimodal neoadjuvant therapy |
| NCT06510374 | Nadofaragene firadenovec | Recombinant adenoviral IFN-α gene therapy | Recruiting | Intermediate-risk NMIBC | Intravesical nadofaragene firadenovec versus observation | Prevention of recurrence and disease progression |
| NCT06545955 | Nadofaragene firadenovec ± chemotherapy/immunotherapy | Combination intravesical gene therapy | Recruiting | BCG-unresponsive NMIBC | Intravesical nadofaragene firadenovec alone or combined with chemotherapy or immunotherapy | Evaluation of enhanced antitumor efficacy and response durability |
| NCT06253845 | CG0070 | Oncolytic adenoviral therapy | Active, not recruiting | Intermediate-risk NMIBC | Intravesical CG0070 following TURBT | Reduction of post-resection recurrence |
| NCT04452591 (BOND-003) | Cretostimogene grenadenorepvec (CG0070) | Oncolytic adenoviral therapy | Active, not recruiting | High-risk BCG-unresponsive NMIBC | Intravesical cretostimogene grenadenorepvec after BCG failure | Evaluation of complete response durability and bladder preservation |
| NCT05232136 | OH2 | Oncolytic HSV-2 therapy | Recruiting | NMIBC | Intravesical OH2 oncolytic viral therapy | Preliminary evaluation of intravesical oncolytic activity |
| NCT06427291 | T3011 | Oncolytic viral therapy | Recruiting | NMIBC | Intravesical instillation of T3011 | Evaluation of intravesical viral therapy efficacy |
| NCT07359235 | KD01 | Recombinant/oncolytic adenoviral therapy | Recruiting | Bladder cancer | Intravesical administration of KD01 | Early clinical assessment of intravesical immunotherapy |
| NCT06632964 | VT-101 | Recombinant/oncolytic adenoviral therapy | Recruiting | NMIBC | VT-101 investigational therapy | Investigation of therapeutic activity in NMIBC |
| NCT06181266 | ZH9 | Salmonella enterica serovar Typhi–based bacterial immunotherapy | Active, not recruiting | High-risk NMIBC | Intravesical ZH9 treatment | Phase 1/1b assessment of dosing, safety, and preliminary efficacy |
| NCT06833073 (V940-011 / INTerpath-011) | Intismeran autogene (V940) + BCG | Personalized mRNA immunotherapy | Recruiting | High-risk NMIBC with CIS | Personalized neoantigen mRNA immunotherapy combined with BCG | Evaluation of recurrence prevention and immune response enhancement |
Ongoing and emerging clinical trials of living cancer therapeutics and oncolytic platforms in bladder cancer.
(Access 1 May 2026).
The corrected Table 2 appears below.
There was a mistake in Figure 4 as published. The title within the schematic contained a typographical error and was given as “Schematic of BCG Mechanisnssof Action in High-Grade Non–Muscle Invasive Bladder Cancer”. The title has been corrected to read “Schematic of BCG Mechanisms of Action in High-Grade Non–Muscle Invasive Bladder Cancer”. The corrected Figure 4 appears below.
There was a mistake in the caption of Figure 1 as published. The publication-year range was erroneously given as “(2010 - 2025)”. The corrected caption of Figure 1 appears below:
Figure 1
Figure 4
“Number of publications using living cancer therapeutic with different types of oncobiotics of UBC from the last 15 years (2011–2025). Publication numbers were calculated using the PubMed database (2026, Jan 1st) using the keywords (oncobiotic OR “living cancer therapeutic” OR “live cancer therapeutic” OR “living therapeutic” OR “live biotherapeutic product” OR “oncolytic virus” OR virotherapy OR bacteriotherapy OR “bacterial therapy” OR “immune-modulating bacteria”) AND (“urinary bladder cancer”[MeSH] OR “bladder cancer” OR “bladder carcinoma” OR “urothelial carcinoma”).”
The reference for Shi et al. (reference 47) was erroneously written as:
“Shi Q, Geng J, Han L, Ji X, Li J, Mu Y, et al. Engineered Salmonella carrying siRNA-PD-1 shrinks orthotopically implanted bladder cancer in rats. J Drug Target. (2025), 1–9. doi: 10.1097/md.0000000000009292”
It should be:
“Shi Q, Geng J, Han L, Ji X, Li J, Mu Y, et al. Engineered Salmonella carrying siRNA-PD-1 shrinks orthotopically implanted bladder cancer in rats. J Drug Target. (2025), 1–9. doi: 10.1080/1061186X.2025.2512619”
The publisher apologizes for the error and the original version of this article has been updated.
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Publisher’s note
All claims expressed in this article are solely those of the authors and do not necessarily represent those of their affiliated organizations, or those of the publisher, the editors and the reviewers. Any product that may be evaluated in this article, or claim that may be made by its manufacturer, is not guaranteed or endorsed by the publisher.
Summary
Keywords
bacteria, bladder cancer, immunotherapy, living cancer therapeutics, oncobiotics, oncolytic viruses, probiotics
Citation
Frontiers Production Office (2026) Correction: Oncobiotics in urinary bladder cancer. A narrative review of living cancer therapeutics. Front. Oncol. 16:1951323. doi: 10.3389/fonc.2026.1951323
Received
28 July 2026
Accepted
28 July 2026
Published
10 September 2026
Approved by
Frontiers Editorial Office, Frontiers Media SA, Switzerland
Volume
16 - 2026
Updates
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© 2026 Frontiers Production Office.
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Disclaimer
All claims expressed in this article are solely those of the authors and do not necessarily represent those of their affiliated organizations, or those of the publisher, the editors and the reviewers. Any product that may be evaluated in this article or claim that may be made by its manufacturer is not guaranteed or endorsed by the publisher.