Mutant myogenin promoter-controlled oncolytic adenovirus selectively kills PAX3-FOXO1-positive rhabdomyosarcoma cells

CDX2 Promoter-Controlled Oncolytic Adenovirus Suppresses Tumor Growth and Liver Metastasis of Colorectal Cancer

Colorectal cancer (CRC) is the second leading cause of cancer death worldwide, and liver metastasis (CRLM) is the most common among its distant metastases. We have recently generated a CDX2 promoter-controlled oncolytic adenovirus (Ad5/3-pCDX2) that showed an anticancer effect for CDX2-positive upper gastrointestinal tumors. Here, we reported the anticancer effect of Ad5/3-pCDX2 for CDX2-positive CRC and CRLM, and its combination efficacy with 5-fluorouracil (5FU) in vitro and in vivo. We used HT29 as CDX2-positive, and LS174T and SW480 as CDX2-negative CRC cell lines. Without 5FU, Ad5/3-pCDX2 killed HT29 but not LS174T and SW480 cells. In vitro, 5FU exposure upregulated CDX2 mRNA levels in all three cell lines. The 5FU combination enhanced the cytocidal effect and virus replication of Ad5/3-pCDX2 in CDX2-negative LS174T. In mouse xenograft models, Ad5/3-pCDX2 monotherapy suppressed the HT29 subcutaneous tumor growth compared to the control group. The 5FU plus Ad5/3-pCDX2 combination therapy showed a remarkable antitumor effect over the efficacy of Ad5/3-pCDX2 monotherapy. In the LS174T subcutaneous tumor, although Ad5/3-pCDX2 monotherapy did not show an antitumor effect, the 5FU plus Ad5/3-pCDX2 combination therapy significantly suppressed the tumor growth compared to the Ad5/3-pCDX2 monotherapy. In mice with HT29 liver metastasis, intrasplenic injection of Ad5/3-pCDX2 induced virus replication in liver tumors and thus successfully attenuated tumor growth. In conclusion, Ad5/3-pCDX2 showed a significant anticancer effect that was enhanced by 5FU treatment in not only CDX2-positive but also negative CRCs. Ad5/3-pCDX2 is a promising therapeutic modality for metastatic CRC such as CRLM.

Development of a novel oncolytic adenovirus controlled by CDX2 promoter for esophageal adenocarcinoma therapy

BACKGROUND

Prognosis of esophageal adenocarcinoma (EAC) is still poor. Therefore, the development of novel therapeutic modalities is necessary to improve therapeutic outcomes in EAC. Here, we report a novel promoter-controlled oncolytic adenovirus targeting CDX2 (Ad5/3-pCDX2) and its specific anticancer effect for EAC.

METHODS

We used OE19, OE33, HT29, MKN28, RH30, and HEL299 cell lines. To establish CDX2 overexpressing OE19 cells, pCMV-GLI1 plasmid was transfected to OE19 (OE19 + GLI1). The virus replication and cytocidal effect of replication competent Ad5/3-pCDX2 were analyzed in vitro. Antitumor effect of Ad5/3-pCDX2 was assessed in xenograft mouse models by intratumoral injection of the viruses. Finally, efficacy of combination therapy with Ad5/3-pCDX2 and 5FU was evaluated.

RESULTS

EAC cells and HT29 showed high mRNA levels of CDX2, but not MKN28, RH30, and HEL299. We confirmed that deoxycholic acid (DCA) exposure enhanced CDX2 expression in EAC cells and OE19 + GLI1 had persistent CDX2 overexpression without DCA. Ad5/3-pCDX2 showed stronger cytocidal effect in OE19 + GLI1 than OE19, whereas Ad5/3-pCDX2 did not kill CDX2-negative cells. Ad5/3-pCDX2 was significantly replicated in EAC cells and the virus replication was higher in OE19 + GLI1 and OE19 with DCA compared to OE19 without DCA exposure. In vivo, Ad5/3-pCDX2 significantly suppressed OE19 tumor growth and the antitumor effect was enhanced in OE19 + GLI1 tumor. In contrast, Ad5/3-pCDX2 did not show significant antitumor effect in MKN28 tumor. Moreover, Ad5/3-pCDX2 significantly increased the efficacy of 5FU in vitro and in vivo.

CONCLUSIONS

Ad5/3-pCDX2 showed specific anticancer effect for EAC, which was enhanced by bile acid exposure. Ad5/3-pCDX2 has promising potential for EAC therapy in the clinical setting.

Intratumoral delivery of a Tim-3 antibody-encoding oncolytic adenovirus engages an effective antitumor immune response in liver cancer

BACKGROUND AND PURPOSE

The use of oncolytic viruses as a gene therapy vector is an area of active biomedical research, particularly in the context of cancer treatment. However, the actual therapeutic success of this approach to tumor elimination remains limited. As such, the present study was developed with the goal of simultaneously enhancing the antitumor efficacy of oncolytic viruses and the local immune response by combining the Ad-GD55 oncolytic adenovirus and an antibody specific for the TIM-3 immune checkpoint molecule (α-TIM-3).

APPROACH AND KEY RESULTS

The results of Virus and cell-mediated cytotoxicity assay, qPCR, and Western immunoblotting showed that Ad-GD55-α-Tim-3 oncolytic adenovirus is capable of inducing α-TIM-3 expression within hepatoma cells upon infection, and Ad-GD55-α-TIM-3 exhibited inhibitory efficacy superior to that of Ad-GD55 when used to treat these tumor cells together with the induction of enhanced intracellular immunity. In vivo experiments revealed that Ad-GD55-α-TIM-3 administration was sufficient to inhibit tumor growth and engage in a more robust local immune response within the simulated tumor immune microenvironment.

CONCLUSION AND IMPLICATIONS

These results highlighted the promising therapeutic effects of Ad-GD55-α-TIM-3 oncolytic adenovirus against HCC in vitro and in vivo. As such, this Ad-GD55-α-TIM-3 oncolytic adenovirus may represent a viable approach to the treatment of hepatocellular carcinoma.

Transforming growth factor-beta (TGF-β) in prostate cancer: A dual function mediator?

Transforming growth factor-beta (TGF-β) is a member of a family of secreted cytokines with vital biological functions in cells. The abnormal expression of TGF-β signaling is a common finding in pathological conditions, particularly cancer. Prostate cancer (PCa) is one of the leading causes of death among men. Several genetic and epigenetic alterations can result in PCa development, and govern its progression. The present review attempts to shed some light on the role of TGF-β signaling in PCa. TGF-β signaling can either stimulate or inhibit proliferation and viability of PCa cells, depending on the context. The metastasis of PCa cells is increased by TGF-β signaling via induction of EMT and MMPs. Furthermore, TGF-β signaling can induce drug resistance of PCa cells, and can lead to immune evasion via reducing the anti-tumor activity of cytotoxic T cells and stimulating regulatory T cells. Upstream mediators such as microRNAs and lncRNAs, can regulate TGF-β signaling in PCa. Furthermore, some pharmacological compounds such as thymoquinone and valproic acid can suppress TGF-β signaling for PCa therapy. TGF-β over-expression is associated with poor prognosis in PCa patients. Furthermore, TGF-β up-regulation before prostatectomy is associated with recurrence of PCa. Overall, current review discusses role of TGF-β signaling in proliferation, metastasis and therapy response of PCa cells and in order to improve knowledge towards its regulation, upstream mediators of TGF-β such as non-coding RNAs are described. Finally, TGF-β regulation and its clinical application are discussed.