The Cell-Penetrating Peptide GV1001 Enhances Bone Formation via Pin1-Mediated Augmentation of Runx2 and Osterix Stability.

Peptide-based drug development is a promising direction due to its excellent biological activity, minimal immunogenicity, high in vivo stability, and efficient tissue penetrability. GV1001, an amphiphilic peptide, has proven effective as an anti-cancer vaccine, but its effect on osteoblast differentiation is unknown. To identify proteins interacting with GV1001, biotin-conjugated GV1001 was constructed and confirmed by mass spectrometry. Proteomic analyses were performed to determine GV1001's interaction with osteogenic proteins. GV1001 was highly associated with peptidyl-prolyl isomerase A and co-immunoprecipitation assays revealed that GV1001 bound to peptidyl-prolyl cis-trans isomerase 1 (Pin1). GV1001 significantly increased alkaline phosphatase (ALP) activity, bone nodule formation, and the expression of osteogenic gene markers. GV1001-induced osteogenic activity was enhanced by Pin1 overexpression and abolished by Pin1 knockdown. GV1001 increased the protein stability and transcriptional activity of Runx2 and Osterix. Importantly, GV1001 administration enhanced bone mass density in the OVX mouse model, as verified by µCT analysis. GV1001 demonstrated protective effects against bone loss in OVX mice by upregulating osteogenic differentiation via the Pin1-mediated protein stabilization of Runx2 and Osterix. GV1001 could be a potential candidate with anabolic effects for the prevention and treatment of osteoporosis.

hTERT Peptide Fragment GV1001 Prevents the Development of Porphyromonas gingivalis-Induced Periodontal Disease and Systemic Disorders in ApoE-Deficient Mice.

GV1001, an anticancer vaccine, exhibits other biological functions, including anti-inflammatory and antioxidant activity. It also suppresses the development of ligature-induced periodontitis in mice. Porphyromonas gingivalis (Pg), a major human oral bacterium implicated in the development of periodontitis, is associated with various systemic disorders, such as atherosclerosis and Alzheimer's disease (AD). This study aimed to explore the protective effects of GV1001 against Pg-induced periodontal disease, atherosclerosis, and AD-like conditions in Apolipoprotein (ApoE)-deficient mice. GV1001 effectively mitigated the development of Pg-induced periodontal disease, atherosclerosis, and AD-like conditions by counteracting Pg-induced local and systemic inflammation, partly by inhibiting the accumulation of Pg DNA aggregates, Pg lipopolysaccharides (LPS), and gingipains in the gingival tissue, arterial wall, and brain. GV1001 attenuated the development of atherosclerosis by inhibiting vascular inflammation, lipid deposition in the arterial wall, endothelial to mesenchymal cell transition (EndMT), the expression of Cluster of Differentiation 47 (CD47) from arterial smooth muscle cells, and the formation of foam cells in mice with Pg-induced periodontal disease. GV1001 also suppressed the accumulation of AD biomarkers in the brains of mice with periodontal disease. Overall, these findings suggest that GV1001 holds promise as a preventive agent in the development of atherosclerosis and AD-like conditions associated with periodontal disease.

GV1001 reduces neurodegeneration and prolongs lifespan in 3xTg-AD mouse model through anti-aging effects.

GV1001, which mimics the activity of human telomerase reverse transcriptase, protects neural cells from amyloid beta (Aß) toxicity and other stressors through extra-telomeric function, as noted in our prior in vitro studies. As per a recent phase II clinical trial, it improves cognitive function in patients with moderate to severe dementia. However, the underlying protective mechanisms remain unclear. This study aimed to investigate the effects of GV1001 on neurodegeneration, senescence, and survival in triple transgenic Alzheimer's disease (3xTg-AD) mice. GV1001 (1 mg/kg) was subcutaneously injected into old 3xTg-AD mice thrice a week until the endpoint for sacrifice, and survival was analysed. Magnetic resonance imaging (MRI) and Prussian blue staining (PBS) were performed to evaluate entry of GV1001 entrance into the brain. Diverse molecular studies were performed to investigate the effect of GV1001 on neurodegeneration and cellular senescence in AD model mice, with a particular focus on BACE, amyloid beta1-42 (Aß1-42), phosphorylated tau, volume of dentate gyrus, ß-galactosidase positive cells, telomere length, telomerase activity, and ageing-associated proteins. GV1001 crossed the blood-brain barrier, as confirmed by assessing the status of ferrocenecarboxylic acid-conjugated GV1001 using magnetic resonance imaging and PBS. GV1001 increased the survival of 3xTg-AD mice. It decreased BACE and Aß1-42 levels, neurodegeneration (i.e., reduced CA1, CA3 and dentate gyrus volume, decreased levels of senescence-associated ß-galactosidase positive cells, and increased telomere length and telomerase activity), and levels of ageing-associated proteins. We suggest that GV1001 exerts anti-ageing effects in 3xTg-AD mice by reducing neurodegeneration and senescence, which contributes to improved survival.

A Recombinant Oncolytic Influenza Virus Carrying GV1001 Triggers an Antitumor Immune Response.

Oncolytic viruses are able to lyse tumor cells selectively in the liver without killing normal hepatocytes, in addition to activating the immune response. Oncolytic virus therapy is expected to revolutionize the treatment of liver cancer, including hepatocellular carcinoma (HCC), one of the most frequent and fatal malignancies. In this study, reverse genetics techniques were exploited to load NA fragments of the A/PuertoRico/8/34 virus (PR8) with GV1001 peptides derived from human telomerase reverse transcriptase. An in vitro assessment of the therapeutic effect of the recombinant oncolytic virus was followed by an in vivo study in mice with HCC. The recombinant virus was verified by sequencing of the recombinant viral gene sequence, and viral virulence was detected by hemagglutination assays and based on the 50% tissue culture infectious dose (TCID50). The morphological structure of the virus was observed by electron microscopy, and GV1001 peptide was localized by cellular immunofluorescence. The selective cytotoxicity of the recombinant oncolytic virus in vitro was demonstrated in cultured HCC cells and normal hepatocytes, as only the tumor cells were killed; the normal cells were not significantly altered. Consistent with the in vitro results, the recombinant oncolytic influenza virus significantly inhibited liver tumor growth in mice in vivo, in addition to inducing an antitumor immune response, including an increase in the number of CD4+ and CD8+ T lymphocytes and, in turn, improving survival. Our results suggest that oncolytic influenza virus carrying GV1001 is a promising immunotherapy in patients with HCC.

GV1001 modulates neuroinflammation and improves memory and behavior through the activation of gonadotropin-releasing hormone receptors in a triple transgenic Alzheimer's disease mouse model.

GV1001 protects neural cells from amyloid-ß (Aß) toxicity and other stressors in in vitro studies and demonstrates clinically beneficial effects in patients with moderate to severe Alzheimer's disease (AD). Here, we investigated the protective effects and mechanism of action of GV1001 in triple transgenic AD (3xTg-AD) mice. We found that GV1001 improved memory and cognition in middle- and old-aged 3xTg-AD mice. Additionally, it reduced Aß oligomer and phospho-tau (Ser202 and Thr205) levels in the brain, and mitigated neuroinflammation by promoting a neuroprotective microglial and astrocyte phenotype while diminishing the neurotoxic ones. In vitro, GV1001 bound to gonadotropin releasing hormone receptors (GnRHRs) with high affinity. Levels of cyclic adenosine monophosphate, a direct downstream effector of activated GnRHRs, increased after GV1001 treatment. Furthermore, inhibition of GnRHRs blocked GV1001-induced effects. Thus, GV1001 might improve cognitive and memory functions of 3xTg-AD mice by suppressing neuroinflammation and reducing Aß oligomers levels and phospho-tau by activating GnRHRs and their downstream signaling pathways.

Retrospective Analysis of the Clinical Characteristics of Patients with Breast Cancer Treated with Telomerase Peptide Immunotherapy Combined with Cytotoxic Chemotherapy.

Purpose: Telomerase activation, a critical step in cancer progression, occurs in approximately 95% of breast cancer cases. Telomerase is an attractive therapeutic target for breast cancer owing to its unique expression pattern. GV1001, a telomerase-derived peptide, is loaded onto human leukocyte antigen (HLA) class II antigen-presenting cells and binds to CD4+ T cell activating immune responses. This study aimed to evaluate the effectiveness and safety of co-administration of GV1001 and cytotoxic chemotherapy in patients with heavily-treated metastatic breast cancer. Patients and methods: We analyzed 63 patients with breast cancer who received both GV1001 and cytotoxic chemotherapy. The GV 1001 administration methods involves 0.56 mg intradermal injection three times during the first week, one time at weeks 2, 3, 4, and 6, and then once every 28 days. The primary endpoint of this study was quality of life according to EORTC QLO-C30 and EQ-5D, while the secondary endpoint was the antitumor response according to RECIST 1.1, progression-free survival, overall survival, and toxicity profile. Results: In 34 patients with HR+ breast cancer evaluable for tumor response, the disease control rate (DCR) and overall response rate (ORR) were 58.8% and 26.4%, respectively. The DCR and ORR were 66.6% and 28.5% in 21 patients with HER-2+ and 50% and 25% in patients with triple-negative breast cancer (TNBC), respectively. The median progression free survival was 10.4, 8.7, and 5.6 months in HR+, HER-2+, TNBC, respectively. The overall survival was 19.7, 13.2, and 9.4 months for patients with HR+, HER-2+, and TNBC, respectively. Most patients had an improved quality of life with statistically significant differences in some variables. The patients in this study experienced no additional toxicities other than the cytotoxic chemotherapy-associated side effects. Conclusion: GV1001 is a relatively safe anticancer vaccine for patients with heavily-treated breast cancer and can to improve the quality of life.

GV1001 Inhibits the Severity of the Ligature-Induced Periodontitis and the Vascular Lipid Deposition Associated with the Periodontitis in Mice.

GV1001, a 16 amino acid peptide derived from the catalytic segment of human telomerase reverse transcriptase, was developed as an anti-cancer vaccine. Subsequently, it was found to exhibit anti-inflammatory and anti-Alzheimer's disease properties. Periodontitis is a risk factor for a variety of systemic diseases, including atherosclerosis, a process in which chronic systemic and vascular inflammation results in the formation of plaques containing lipids, macrophages, foam cells, and tissue debris on the vascular intima. Thus, we investigated the effect of GV1001 on the severity of ligature-induced periodontitis, vascular inflammation, and arterial lipid deposition in mice. GV1001 notably reduced the severity of ligature-induced periodontitis by inhibiting gingival and systemic inflammation, alveolar bone loss, and vascular inflammation in wild-type mice. It also significantly lowered the amount of lipid deposition in the arterial wall in ApoE-deficient mice receiving ligature placement without changing the serum lipid profile. In vitro, we found that GV1001 inhibited the Receptor Activator of NF-κB ligand (RANKL)-induced osteoclast formation and tumor necrosis factor-α (TNF-α)-induced phenotypic changes in endothelial cells. In conclusion, our study suggests that GV1001 prevents the exacerbation of periodontitis and atherosclerosis associated with periodontitis partly by inhibiting local, systemic, and vascular inflammation and phenotypic changes of vascular endothelial cells.

Effects of GV1001 on Language Dysfunction in Patients With Moderate-to-Severe Alzheimer's Disease: Post Hoc Analysis of Severe Impairment Battery Subscales.

Background and Purpose: The efficacy and safety of GV1001 have been demonstrated in patients with moderate-to-severe Alzheimer's disease (AD). In this study, we aimed to further demonstrate the effectiveness of GV1001 using subscales of the Severe Impairment Battery (SIB), which is a validated measure to assess cognitive function in patients with moderate-to-severe AD. Methods: We performed a post hoc analysis of data from a 6 month, multicenter, phase 2, randomized, double-blind, placebo-controlled trial with GV1001 (ClinicalTrials.gov, NCT03184467). Patients were randomized to receive either GV1001 or a placebo for 24 weeks. In the current study, nine subscales of SIB-social interaction, memory, orientation, language, attention, praxis, visuospatial ability, construction, and orientation to name- were compared between the treatment (GV1001 1.12 mg) and placebo groups at weeks 12 and 24. The safety endpoints for these patients were also determined based on adverse events. Results: In addition to the considerable beneficial effect of GV1001 on the SIB total score, GV1001 1.12 mg showed the most significant effect on language function at 24 weeks compared to placebo in both the full analysis set (FAS) and per-protocol set (PPS) (p=0.017 and p=0.011, respectively). The rate of adverse events did not differ significantly between the 2 groups. Conclusions: Patients with moderate-to-severe AD receiving GV1001 had greater language benefits than those receiving placebo, as measured using the SIB language subscale.

A novel telomerase-derived peptide GV1001-mediated inhibition of angiogenesis: Regulation of VEGF/VEGFR-2 signaling pathways.

GV1001, a human telomerase reverse transcriptase catalytic subunit-derived 16-mer peptide, has been developed as a novel anticancer vaccine against various cancers including pancreatic cancer. In the current study, we demonstrate the regulatory roles and mechanisms of GV1001 in endothelial cell responses in vitro and microvessel sprouting ex vivo. GV1001 markedly inhibits vascular endothelial growth factor-A (VEGF-A)-stimulated endothelial cell permeability, proliferation, migration, invasion, tube formation as well as microvessel outgrowth from rat aortic rings. These anti-angiogenic effects of GV1001 were associated with the inhibition of VEGF-A/VEGFR-2 signaling pathways, redistribution of vascular endothelial-cadherin to cell-cell contacts, and down-regulation of VEGFR-2 and matrix metalloproteinase-2. Furthermore, GV1001 suppresses the proliferation and invasion of non-small cell lung cancer cells, and the release of VEGF from the cells, suggesting the regulatory role of GV1001 in tumor-derived angiogenesis as well as cancer cell growth and progression. Collectively, our study reports the pharmacological potential of GV1001 in the regulation of angiogenesis, and warrants further evaluation and development of GV1001 as a promising therapeutic agent for a variety of angiogenesis-related diseases including cancer.

A phase II study of chemotherapy in combination with telomerase peptide vaccine (GV1001) as second-line treatment in patients with metastatic colorectal cancer.

Background: GV1001 is a human telomerase peptide vaccine that induces a CD4/CD8 T-cell response against cancer cells, thereby affording an immunological anti-tumor effect. Here, we evaluated the efficacy and safety of GV1001 in combination with chemotherapy in patients with metastatic colorectal cancer who had failed first-line chemotherapy. Methods: This multicenter, non-randomized, single-arm phase II study recruited recurrent or metastatic colorectal cancer patients with measurable disease who had failed first-line chemotherapy. Patients received GV1001 and chemotherapy concomitantly based on a pre-established schedule. Cytotoxic chemotherapy and targeted agents (bevacizumab, cetuximab, or aflibercept) were allowed to be used at the discretion of the investigator. The primary endpoint was the disease control rate; secondary endpoints were the objective response rate, progression-free survival, overall survival, and safety outcomes. The baseline serum eotaxin level (a potential predictive biomarker of GV1001) was analyzed. To determine whether an adequate immune response had been induced, a delayed-type hypersensitivity test and a T-cell proliferation test were performed. Results: From May 13, 2015 to October 13, 2020, 56 patients with recurrent or metastatic colorectal cancer treated in seven hospitals of South Korea were enrolled. The median patient age was 64 years (range, 29-82 years); 67.9% were men. Of all patients, 66.1% had left-side colorectal cancer and the RAS mutation was present in 25%. The disease control rate and the objective response rates were 90.9% (95% confidence interval [CI]: 82.4-99.4%) and 34.1% (95% CI, 20.1-48.1%), respectively. The median progression-free survival was 7.1 months (95% CI, 5.2-9.1 months) and the median overall survival was 12.8 months (95% CI, 9.9-15.8 months). The most common all-grade adverse events were neutropenia (48.2%), nausea (26.8%), neuropathy (25.0%), stomatitis (21.4%), and diarrhea (21.4%). Immune response analysis showed that no patient had positive delayed-type hypersensitivity test results; antigen-specific T-cell proliferation was observed in only 28% of patients. The baseline eotaxin level was not associated with any efficacy outcome. Conclusion: Although no clear GV1001-specific immune response was observed, the addition of GV1001 vaccination to chemotherapy was tolerable and associated with modest efficacy outcomes.

Anti-metastatic effect of GV1001 on prostate cancer cells; roles of GnRHR-mediated Gαs-cAMP pathway and AR-YAP1 axis.

BACKGROUND: Gonadotropin-releasing hormone receptor (GnRHR) transmits its signal via two major Gα-proteins, primarily Gαq and Gαi. However, the precise mechanism underlying the functions of Gαs signal in prostate cancer cells is still unclear. We have previously identified that GV1001, a fragment of the human telomerase reverse transcriptase, functions as a biased GnRHR ligand to selectively stimulate the Gαs/cAMP pathway. Here, we tried to reveal the potential mechanisms of which GV1001-stimulated Gαs-cAMP signaling pathway reduces the migration and metastasis of prostate cancer (PCa) cells. METHODS: The expression of epithelial-mesenchymal transition (EMT)-related genes was measured by western-blotting and spheroid formation on ultra-low attachment plate was detected after GV1001 treatment. In vivo Spleen-liver metastasis mouse model was used to explore the inhibitory effect of GV1001 on metastatic ability of PCa and the transwell migration assay was performed to identify whether GV1001 had a suppressive effect on cell migration in vitro. In order to demonstrate the interaction between androgen receptor (AR) and YAP1, co-immunoprecipitation (co-IP), immunofluorescence (IF) staining, chromatin immunoprecipitation (ChIP) were performed in LNCaP cells with and without GV1001 treatment. RESULTS: GV1001 inhibited expression of EMT-related genes and spheroid formation. GV1001 also suppressed in vivo spleen-liver metastasis of LNCaP cells as well as cell migration in vitro. GV1001 enhanced the phosphorylation of AR and transcription activity of androgen response element reporter gene through cAMP/protein kinase A pathway. Moreover, GV1001 increased Ser-127 phosphorylation of YAP1 and its ubiquitination, and subsequently decreased the levels of AR-YAP1 binding in the promoter region of the CTGF gene. In contrast, both protein and mRNA levels of NKX3.1 known for tumor suppressor gene and AR-coregulator were upregulated by GV1001 in LNCaP cells. YAP1 knockout using CRISPR/Cas9 significantly suppressed the migration ability of LNCaP cells, and GV1001 did not affect the cell migration of YAP1-deficient LNCaP cells. On the contrary, cell migration was more potentiated in LNCaP cells overexpressing YAP5SA, a constitutively active form of YAP1, which was not changed by GV1001 treatment. CONCLUSIONS: Overall, this study reveals an essential role of AR-YAP1 in the regulation of PCa cell migration, and provides evidence that GV1001 could be a novel GnRHR ligand to inhibit metastasis of PCa via the Gαs/cAMP pathway.

Neuroprotective Effects of GV1001 in Animal Stroke Model and Neural Cells Subject to Oxygen-Glucose Deprivation/Reperfusion Injury.

BACKGROUND AND PURPOSE: Previous studies have revealed the diverse neuroprotective effects of GV1001. In this study, we investigated the effects of GV1001 on focal cerebral ischemia-reperfusion injury (IRI) in rats and oxygen-glucose deprivation/reoxygenation (OGD/R)-induced injury in neural stem cells (NSCs) and cortical neurons. METHODS: Focal cerebral IRI was induced by transient middle cerebral artery occlusion (MCAO). Brain diffusion-weighted imaging (DWI) was performed 2 hours after occlusion, and a total of 37 rats were treated by reperfusion with GV1001 or saline 2 hours after occlusion. Fluid-attenuated inversion recovery (FLAIR) magnetic resonance imaging, immunohistochemistry, and neurobehavioral function analyses were performed. Additionally, OGD/R-injured NSCs and cortical neurons were treated with different GV1001 concentrations. Cell viability, proliferation, migration, and oxidative stress were determined by diverse molecular analyses. RESULTS: In the stroke model, GV1001 protected neural cells against IRI. The most effective dose of GV1001 was 60 µM/kg. The infarct volume on FLAIR 48 hours after MCAO compared to lesion volume on DWI showed a significantly smaller ratio in the GV1001-treated group. GV1001-treated rats exhibited better behavioral functions than the saline-treated rats. Treatment with GV1001 increased the viability, proliferation, and migration of the OGD/R-injured NSCs. Free radicals were significantly restored by treatment with GV1001. These neuroprotective effects of GV1001 have also been demonstrated in OGD/R-injured cortical neurons. CONCLUSIONS: The results suggest that GV1001 has neuroprotective effects against IRI in NSCs, cortical neurons, and the rat brain. These effects are mediated through the induction of cellular proliferation, mitochondrial stabilization, and anti-apoptotic, anti-aging, and antioxidant effects.

Efficacy and safety of GV1001 in patients with moderate-to-severe Alzheimer's disease already receiving donepezil: a phase 2 randomized, double-blind, placebo-controlled, multicenter clinical trial.

BACKGROUND: Our previous studies showed that GV1001 has various protective effects against ß-amyloid and other stressors. Based on these findings, we hypothesized that GV1001 might have beneficial effects in patients with Alzheimer's disease (AD). METHODS: A phase 2, double-blind, parallel-group, placebo-controlled, 6-month randomized clinical trial was performed to evaluate the safety and efficacy of subcutaneously administered GV1001. Between September 2017 and September 2019, 13 centers in South Korea recruited participants. A total of 106 patients were screened, and 96 patients with moderate-to-severe AD were randomized 1:1:1 to the placebo (group 1, n = 31), GV1001 0.56 mg (group 2, n = 33), and 1.12 mg (group 3, n = 32) groups. GV1001 was administered every week for 4 weeks (4 times), followed by every 2 weeks until week 24 (10 times). The primary endpoint was the change in the Severe Impairment Battery (SIB) score from baseline to week 24. The key secondary efficacy endpoints were the change in the Clinical Dementia Rating Sum of Box (CDR-SOB), Alzheimer's Disease Cooperative Study-Activities of Daily Living (ADCS-ADL), Neuropsychiatric Inventory (NPI), Mini-Mental State Examination, and Global Deterioration Scale scores. The safety endpoints were also assessed based on adverse events, laboratory test results, vital signs, and other observations related to safety. RESULTS: Group 3 showed less decrease in the SIB score at 12 and 24 weeks compared with group 1 (P < 0.05). These were not significantly observed in group 2. Among the secondary endpoints, only the NPI score showed significantly better improvement in group 2 than in group 3 at week 12; however, there were no other significant differences between the groups. Although the ADCS-ADL and CDR-SOB scores showed a pattern similar to SIB scores, a statistically significant result was not found. Adverse events were similar across all three groups. CONCLUSIONS: The results indicate that GV1001 1.12 mg met the primary endpoint of a statistically significant difference. GV1001 was well tolerated without safety concerns. This study warrants a larger clinical trial. TRIAL REGISTRATION: ClinicalTrials.gov NCT03184467 . Registered on June 12, 2017.

GV1001 interacts with androgen receptor to inhibit prostate cell proliferation in benign prostatic hyperplasia by regulating expression of molecules related to epithelial-mesenchymal transition.

Prostate cell proliferation, driven by testosterone, is a major characteristic of benign prostatic hyperplasia (BPH). GV1001, a human telomerase reverse transcriptase catalytic subunit, is an injectable formulation used as a cancer vaccine. It functions as a cell penetrating peptide to regulate cell proliferation. Here, we found that GV1001 effectively suppressed proliferation of prostatic stromal myofibroblasts (WPMY-1) and prostatic epithelial cells (RWPE-1 and WPE-NA22) treated with dihydrotestosterone. Also, GV1001 bound to androgen receptors (ARs) in the cytosol of stromal and epithelial cells. In an experimental animal model implanted with an infusion pump for spontaneous and continuous release of testosterone, revealed that GV1001 reduced prostatic hypertrophy and inhibited the cell proliferation and the expression of Ki67, proliferating cell nuclear antigen, and prostate specific antigen. In addition, GV1001 prevented fibrosis of the prostate by downregulating expression of prostatic epithelial-mesenchymal transition (EMT)-related proteins such as transforming growth factor (TGF)-ß, Snail, Slug, N-cadherin, and Vimentin, and by up-regulating E-cadherin. Taken together, these results suggest that GV1001, which suppresses TGF-ß-mediated EMT by outcompeting testosterone for binding to AR, is a potential therapeutic drug for BPH accompanied by prostatic fibrosis.

Outcomes of Peptide Vaccine GV1001 Treatment in a Murine Model of Acute Noise-Induced Hearing Loss.

Noise-induced hearing loss (NIHL) is primarily caused by damage to cochlear hair cells, associated with synaptopathy. The novel cell-penetrating peptide GV1001, an antitumor agent, also has antioxidant and anti-inflammatory effects, and is otoprotective in a murine model of kanamycin-induced ototoxicity. Here, we explored whether GV1001 attenuated NIHL, and the underlying mechanism at play. We established an NIHL model by exposing 4- to 6-week-old C57/BL6 mice to white noise at 120 dB SPL for 2 h, resulting in a significant permanent threshold shift (PTS). We then subcutaneously injected saline (control), GV1001, or dexamethasone immediately after cessation of PTS-noise exposure and evaluated the threshold shifts, structural damages to outer hair cells (OHCs), and ribbon synapses. We also verified whether GV1001 attenuates oxidative stress at the level of lipid peroxidation or protein nitration in OHCs 1 h after exposure to white noise at 120 dB SPL. GV1001-treated mice exhibited significantly less hearing threshold shifts over 2 weeks and preserved OHCs and ribbon synapses compared with controls. Similarly, dexamethasone-treated mice showed comparable protection against NIHL. Importantly, GV1001 markedly attenuated oxidative stress in OHCs. Our findings suggest that GV1001 may protect against NIHL by lowering oxidative stress and may serve as preventive or adjuvant treatment.

GV1001 inhibits cell viability and induces apoptosis in castration-resistant prostate cancer cells through the AKT/NF-κB/VEGF pathway.

Purpose: We examined the effect of GV1001 in castration castration-resistant prostate cancer (CRPC) cell growth and invasion and explored the potential molecular mechanisms of action. Materials and Methods: The in vitro anti-cancer effects of GV1001 in CRPC cells were examined using cell viability assay, TUNEL assay, and flow cytometry analysis. To evaluate the effects of GV1001 on different steps of angiogenesis, wound healing assay, transwell invasion assay, endothelial cell tube formation assay, and western blot analysis were performed. Finally, the anti-cancer effects of GV1001 on tumor growth in vivo were examined in a CRPC xenograft model. Results: GV1001 inhibited cell viability and induced apoptosis in CRPC cells in vitro, accompanied by down-regulation of Bcl-2 and caspase-3. GV1001 also inhibited different steps of angiogenesis, such as migration, invasion, and endothelial tube formation, along with decreased expression of MMP-2, MMP-9, and CD31 and increased expression of TIMP-1 and TIMP-2. Mechanistically, GV1001 significantly decreased the levels of phosphorylated AKT, phosphorylated p65, and VEGF in CRPC cells in a dose-dependent manner. GV1001 was effective in suppressing tumor growth and inducing apoptosis in a CRPC xenograft mouse model. Conclusions: Our data demonstrated that GV1001 inhibited cell viability, induced apoptosis, and inhibited angiogenesis in CRPC cells by inhibition of the AKT/NF-κB/VEGF signaling pathway.

Anti-cancer effect of GV1001 for prostate cancer: function as a ligand of GnRHR.

GV1001, a 16-amino acid fragment of the human telomerase reverse transcriptase catalytic subunit (hTERT), has been developed as an injectable formulation of cancer vaccine. Here, we revealed for the first time that GV1001 is a novel ligand for gonadotropin-releasing hormone receptor (GnRHR). The docking prediction for GV1001 against GnRHR showed high binding affinity. Binding of GV1001 to GnRHR stimulated the Gαs-coupled cAMP signaling pathway and antagonized Gαq-coupled Ca2+ release by leuprolide acetate (LA), a GnRHR agonist. Repeated injection of GV1001 attenuated both serum testosterone level and seminal vesicle weight via desensitization of hypothalamic-pituitary-gonadal (HPG) axis. We then tested whether GV1001 has an inhibitory effect on tumor growth of LNCaP cells, androgen receptor-positive human prostate cancer (PCa) cells. GV1001 significantly inhibited tumor growth and induced apoptosis in LNCaP-implanted xenografts. Interestingly, mRNA expressions of matrix metalloproteinase 2 and matrix metalloproteinase 9 were suppressed by GV1001, but not by LA. Moreover, GV1001 significantly inhibited the proliferation and migration of PCa cells and induced apoptosis in a concentration-dependent manner. Our findings suggest that GV1001 functions as a biased GnRHR ligand to selectively stimulate the Gαs/cAMP pathway, with anti-proliferative and anti-migratory effects on human PCa.

A randomised, placebo-controlled, multicentre, Phase 2 clinical trial to evaluate the efficacy and safety of GV1001 in patients with benign prostatic hyperplasia.

OBJECTIVES: To evaluate the efficacy and safety of three dosing schemes of GV1001 in patients with benign prostatic hyperplasia (BPH). PATIENTS AND METHODS: Eligible patients were men aged ≥50 years, with an International Prostate Symptom Score (IPSS) of ≥13, maximum urinary flow rate (Qmax ) of 5-15 mL/s, post-void residual urine volume (PVR) of ≤200 mL, and prostate volume of ≥30 mL. After a 4 week run-in period, patients were randomly assigned to one of three treatment schedules: Group 1, GV1001 0.4 mg, 2-week interval; Group 2, GV1001 0.56 mg, 2-week interval; Group 3, GV1001 0.56 mg, 4-week interval) or placebo (Group 4). The eligible patients were administered GV1001 or placebo, for a total of seven intradermal injections that were administered at 2-week intervals at weeks 0, 2, 4, 6, 8, 10, and 12. Treatment continued for 12 weeks, and efficacy was evaluated at weeks 4, 8, 12, 13, and 16. Safety was evaluated throughout the 16-week period. The primary efficacy variable was change from baseline (CFB) in total IPSS. Secondary endpoints were CFB in Qmax , PVR, prostate volume, International Index of Erectile Function score, plasma testosterone level, dihydrotestosterone level, and prostate-specific antigen level. RESULTS: A total of 161 patients were included (Group 1, n = 41; Groups 2-4, n = 40). Most patients (88.8%) received all planned doses of the study treatment. At week 13, a statistically significant difference in the mean CFB in IPSS was seen in GV1001 treatment Groups 1 and 2 vs the control group for the full analysis population (-3.5 [control] vs -7.2 and -6.8 in Groups 1 and 2, respectively; both P < 0.05). There were also statistically significant differences in CFB at weeks 8, 12, 13, and 16 in treatment Groups 1 and 2 vs control in the per-protocol population. There was a statistically significant reduction in prostate gland volume at week 16 vs control in all treatment groups (0.8 [control] vs -4.6, -2.5, and -4.2 mL in Groups 1-3, respectively; all P < 0.05). There were no statistically significant differences found in other secondary outcome measures. Adverse event (AE) reporting was similar across all four groups. No treatment-emergent AEs were considered to be related to the study drug. CONCLUSIONS: The results indicate that GV1001 was effective and well tolerated, and may provide potential beneficial effects in patients with BPH. Compared with medical therapies that require daily dosing, the convenient dosing regimen of GV1001 may provide greater patient adherence. Further investigation of these observations will require large-scale clinical evaluation.

Novel Peptide Vaccine GV1001 Rescues Hearing in Kanamycin/Furosemide-Treated Mice.

The cell-penetrating peptide GV1001 has been investigated as an anticancer agent and recently demonstrated anti-oxidant and anti-inflammatory effects. It has shown a protective effect on a kanamycin (KM)-induced ototoxicity mouse model. In the present study, we administered GV1001 at different time points after inducing hair cell damage, and examined if it rescues hair cell loss and restores hearing. A deaf mouse model was created by intraperitoneal injection of KM and furosemide. First, to test the early temporal change of hearing and extent of hair cell damage after KM and furosemide injection, hearing and outer hair cells (OHCs) morphology were evaluated on day 1, day 2 and day 3 after injection. In the second experiment, following KM and furosemide injection, GV1001, dexamethasone, or saline were given for three consecutive days at different time points: D0 group (days 0, 1, and 2), D1 group (days 1, 2, and 3), D3 group (days 3, 4, and 5) and D7 group (days 7, 8, and 9). The hearing thresholds were measured at 8, 16, and 32 kHz before ototoxic insult, and 7 days and 14 days after KM and furosemide injection. After 14 days, each turn of the cochlea was imaged to evaluate OHCs damage. GV1001-treated mice showed significantly less hearing loss and OHCs damage than the saline control group in the D0, D1 and D3 groups (p < 0.0167). However, there was no hearing restoration or intact hair cell in the D7 group. GV1001 protected against cochlear hair cell damage, and furthermore, delayed administration of GV1001 up to 3 days rescued hair cell damage and hearing loss in KM/furosemide-induced deaf mouse model.

Telomerase based anticancer immunotherapy and vaccines approaches.

Telomerase is a Reverse Transcriptase that maintains the telomere length. It is absent in most somatic cells but is found in stem cells, germ cells and around 90% of cancers. It plays a crucial role in developing and maintaining cancer cells. Telomerase, a HLA class-I antigen, is able to stimulate cell mediated immune response by inducing cytotoxic T-cells. This property of telomerase is being exploited in targeting cancers by host's own immune responses; stimulated by various Human Telomerase Reverse Transcriptase (hTERT) derived vaccines. Many approaches and studies including clinical trials have shown effective anticancer responses of these vaccines, without toxicity to non cancer cells. In this article we have compiled different hTERT based anticancer immunotherapy approaches, vaccines and their performances.