Recombinant Adenoviral Human P53 Research Articles

Recombinant human adenovirus p53 combined with transcatheter arterial chemoembolization for liver cancer: A meta-analysis.

To compare the clinical curative effects, survival and complications of recombinant human adenovirus-p53 (rAd-p53) combined with transcatheter arterial chemoembolization (TACE) versus TACE for the treatment of liver cancer. We searched all the eligible studies of rAd-p53 plus TACE versus control group had only TACE in the treatment of liver cancer, which were retrieved from CNKI, Wanfang database, CBM, VIP, PubMed, EMBase, The Chrance of Library, Web of Science from its inception to august 2022. A total of 17 studies were included, which involved 1045 patients. The results of the meta analysis indicated that the the rAd-p53combined with TACE markedly improved the patients' complete remission(OR = 2.19, 95% CI:1.13-4.22, P = 0.02), partial remission (OR = 2.22, 95% CI:1.67-2.94, P<0.00001), objective tumor response rate (OR = 2.58, 95% CI:1.95-3.41, P<0.00001) and disease control rate(OR = 2.39, 95% CI:1.65-3.47, P<0.00001) compared with TACE alone. And our results showed that rAd-p53combined with TACE had better survival benefit [6-month OS (OR = 3.41, 95% CI: 1.62-7.14, p = 0.001); 1-year OS (OR = 1.95, 95% CI: 1.28-2.96, p = 0.002)] and better quality of life(MD = 5.84, 95% CI:2.09-9.60, P = 0.002). In addition, the immunity of the patients was enhanced by the combination therapy, as demonstrated by the increase in the ratio of CD4+ to CD4+/CD8+. In adverse effects, except for fever in the TACE combined with rAd-p53 group, which was higher than that in the TACE group(OR = 2.62, 95% CI:2.02-3.49, P<0.00001), all other adverse effects were lower in the TACE combined with rAd-p53 group than in the TACE group. RAd-p53 combined with TACE for liver cancer showed significant advantages in terms of clinical efficacy, survival rate, and safety compared to the TACE alone, and effectively improved patient quality of life and immune function. https://inplasy.com/inplasy-2022-9-0127/.

Recombinant human p53 adenovirus injection combined with Bortezomib inhibits proliferation and promotes apoptosis in multiple myeloma

BackgroundMultiple myeloma (MM) is a B-cell malignancy characterized by abnormal proliferation of clonal plasma cells in the bone marrow, the incidence of which has further increased in recent years. In multiple myeloma, wild-type functional p53 is often inactivated or dysregulated. Therefore, this study aimed to investigate the role of p53 knockdown or overexpression in multiple myeloma and the therapeutic effect of recombinant adenovirus-p53 (rAd-p53) in combination with Bortezomib. MethodsSiRNA p53 and rAd-p53 were used to knock down and overexpress p53. RT-qPCR was used to detect gene expression, and western blotting (WB) was used to detect protein expression levels. We also constructed wild-type multiple myeloma cell line-MM1S cell xenograft tumor models and explored the effects of siRNA-p53, rAd-p53, and Bortezomib on multiple myeloma in vivo and in vitro. H&E staining and KI67 immunohistochemical staining were used to assess the anti-myeloma effects of recombinant adenovirus and Bortezomib in vivo. ResultsThe designed siRNA p53 effectively led to the knockdown of the p53 gene, while rAd-p53 could significantly achieve p53 overexpression. p53 gene inhibited MM1S cell proliferation and promoted apoptosis of wild-type multiple myeloma cell line MM1S. P53 gene inhibited tumor proliferation in vitro by promoting p21 expression and reducing cell cycle protein B1 expression of MM1S. P53 gene overexpression could inhibit tumor growth in vivo. Injection of rAd-p53 in tumor models inhibited tumor development through p21- and cyclin B1-mediated cell proliferation and apoptosis regulation. ConclusionsWe found that overexpression of p53 inhibits MM tumor cell survival and proliferation in vivo and in vitro. Furthermore, the combination of rAd-p53 and Bortezomib significantly improved the efficacy, which provides a new possibility for more effective treatment of MM.

Applications of Recombinant Adenovirus-p53 Gene Therapy for Cancers in the Clinic in China.

Suppression of TP53 function is nearly ubiquitous in human cancers, and a significant fraction of cancers have mutations in the TP53 gene itself. Therefore, the wild-type TP53 gene has become an important target gene for transformation research of cancer gene therapy. In 2003, the first anti-tumor gene therapy drug rAd-p53 (recombinant human p53 adenovirus), trade name Gendicine™, was approved by the China Food and Drug Administration (CFDA) for treatment of head and neck squamous cell carcinoma (HNSCC) in combination with radiotherapy. The recombinant human TP53 gene is delivered into cancer cells by an adenovirus vector constructed to express the functional p53 protein. Although the only currently approved used of Gendicine is in combination with radiotherapy for treatment of HNSCC, clinical studies have been carried out for more than 20 other applications of Gendicine in treating cancer, including treatment of advanced lung cancer, advanced liver cancer, malignant gynecological tumors, and soft tissue sarcomas. Currently more than 30,000 patients have been treated with Gendicine. This review provides an overview of the clinical applications of Gendicine in China. We summarize a total of 48 studies with 2,561 patients with solid tumors, including 34 controlled clinical studies and 14 open clinical studies, i.e., clinical studies without a control group. There are 11 studies for head and neck cancer, 10 for liver cancer, 6 for malignant gynecological tumors, 4 for non-small cell lung cancer, 4 for soft tissue sarcoma, 4 for malignant effusion, 2 for gastrointestinal tumors, and 7 for other types of cancer. In all the reported clinical studies, the most common side effect was self-limited fever. Intratumoral injection and intra-arterial infusion were the most common routes of administration. Overall, Gendicine combined with chemotherapy, radiotherapy, or other conventional treatment regimens demonstrated significantly higher response rates compared to standard therapies alone. Some of the published studies also showed that Gendicine combination regimens demonstrated longer progression-free survival times than conventional treatments alone. To date, Gendicine has been clinically used in China for treatment of cancers other than HNSCC for more than ten years, mainly for patients with advanced or unresectable malignant tumors. However, the establishment of standard treatment regimens using TP53 gene therapy is still needed in order to advance its use in clinical practice.

Combined effect of recombinant human adenovirus p53 and curcumin in the treatment of liver cancer.

The development of an effective therapeutic intervention for liver cancer is a worldwide challenge that remains to be adequately addressed. Of note, TP53, which encodes the p53 protein, is an important tumor suppressor gene, 61% of TP53 is functionally inactivated in liver cancer. Recombinant human adenovirus p53 (rAd-p53) is the first commercial product that has been used for gene therapy. In the present study, the combined mechanistic effects of rAd-p53 and curcumin, a naturally occurring compound with previously reported anti-inflammatory, antioxidant and anti-cancer properties, were assessed in liver cancer cells, using HepG2 cells as the model cell line. The administration of either curcumin or rAd-p53 promoted apoptosis, suppressed epithelial-mesenchymal transition (EMT) and blocked G2/M phase progression in HepG2 cells, which were potentiated further when both agents were applied together. Combined rAd-p53 and curcumin treatment resulted in higher p53 (P<0.01) and p21 (P<0.01) expression compared with rAd-p53 or curcumin were added alone, suggesting an additive effect on TP53 expression. Additionally, curcumin and rAd-p53 were demonstrated to regulate the activation of mitogen-activated protein kinases (MAPKs) ERK1/2, p38 MAPK and JNK. These results indicated that the combination of rAd-p53 with curcumin synergistically potentiates apoptosis and inhibit EMT compared with either rAd-p53 or curcumin treatment alone via the regulation of TP53 regulation. Mechanistically, this effect on TP53 expression may involve the ERK1/2, p38 MAPK and JNK signaling pathways. The current study provides new insights that can potentially advance the development of therapeutic strategies for liver cancer treatment.

Retraction: Recombinant Human Adenovirus-p53 Injection Induced Apoptosis in Hepatocellular Carcinoma Cell Lines Mediated by p53-Fbxw7 Pathway, Which Controls c-Myc and Cyclin E.

Retraction: Recombinant Human Adenovirus-p53 Injection Induced Apoptosis in Hepatocellular Carcinoma Cell Lines Mediated by p53-Fbxw7 Pathway, Which Controls c-Myc and Cyclin E.

The First Approved Gene Therapy Product for Cancer Ad-p53 (Gendicine): 12 Years in the Clinic.

Gendicine (recombinant human p53 adenovirus), developed by Shenzhen SiBiono GeneTech Co. Ltd., was approved in 2003 by the China Food and Drug Administration (CFDA) as a first-in-class gene therapy product to treat head and neck cancer, and entered the commercial market in 2004. Gendicine is a biological therapy that is delivered via minimally invasive intratumoral injection, as well as by intracavity or intravascular infusion. The wild-type (wt) p53 protein expressed by Gendicine-transduced cells is a tumor suppressor that is activated by cellular stress, and mediates cell-cycle arrest and DNA repair, or induces apoptosis, senescence, and/or autophagy, depending upon cellular stress conditions. Based on 12 years of commercial use in >30,000 patients, and >30 published clinical studies, Gendicine has exhibited an exemplary safety record, and when combined with chemotherapy and radiotherapy has demonstrated significantly higher response rates than for standard therapies alone. In addition to head and neck cancer, Gendicine has been successfully applied to treat various other cancer types and different stages of disease. Thirteen published studies that include long-term survival data showed that Gendicine combination regimens yield progression-free survival times that are significantly longer than standard therapies alone. Although the p53 gene is mutated in >50% of all human cancers, p53 mutation status did not significantly influence efficacy outcomes and long-term survival rate for Ad-p53-treated patients. To date, Shenzhen SiBiono GeneTech has manufactured 41 batches of Gendicine in compliance with CFDA QC/QA requirements, and 169,571 vials (1.0 × 1012 vector particles per vial) have been used to treat patients. No serious adverse events have been reported, except for vector-associated transient fever, which occurred in 50-60% of patients and persisted for only a few hours. The manufacturing accomplishments and clinical experience with Gendicine, as well as the understanding of its cellular mechanisms of action and implications, could provide valuable insights for the international gene therapy community and add valuable data to promote further developments and advancements in the gene therapy field.

Surgery combined with adenoviral p53 gene therapy for treatment of non-small cell lung cancer: a phase II study.

ObjectiveTo assess the efficacy of radical surgery combined with recombinant adenoviral human p53 (rAd-p53) gene therapy in treatment of resectable non-small cell lung cancer.MethodA total of 163 patients with resectable NSCLC meeting the inclusion criteria were randomly assigned to two groups: radical surgery alone (S) and radical surgery plus surgical wound surface injection of 2 x 1012 rAd-p53 units (SP). All patients were followed up for at least 3 years for efficacy and safety. Study endpoints were loco-regional recurrence or distant metastasis (Rec-Met) rate as primary endpoints, and progression free survival (PFS), overall survival (OS) and safety assessments as secondary endpoints.ResultsRecurrence or metastasis (Rec/Met) after surgery were 24/82 (29.27%) in SP group and 37/81 (45.68%) in S group. The difference in the Rec/Met rate was statistically significant (p = 0.0304) by chi-square test. The hazard ratios after adjusting of age and disease stage (S vs. SP) of PFS and OS are 1.772 (95% CI, 1.102 to 2.848) and 2.047 (95% CI, 1.109 to 3.377), respectively. The 3 years PFS and OS for SP vs. S were 71.9% vs. 46.9%, and 88.4% vs. 67.0%, respectively. Differences in PFS and OS between two treatment groups were significant with the p values of 0.0165 and 0.0191, respectively, using Log-Rank test.ConclusionsThe wound surface injection of rAd-p53 showed efficacious effects in preventing recurrence or metastasis and improving PFS and OS after a radical surgery in patients with NSCLC.

Recombinant human adenovirus-p53 improves the outcome of mid-late stage pancreatic cancer via arterial infusion.

The present study aimed to investigate the therapeutic efficacy and clinical value of recombinant human adenovirus-p53 (rAd-p53) perfusion via the pancreatic artery for the treatment of mid-late stage pancreatic cancer. rAd-p53 (2×1012 virus particles) in 6 ml normal saline was pushed (intravenous bolus) into the gastroduodenal and superior pancreaticoduodenal arteries via interventional superselection, with the catheter retained for subsequent drug administration at a 3-day interval for 4 cycles. Tumor changes in all patients were observed to evaluate tumor response by computed tomography (CT) at 2, 8 and 16 weeks post-treatment. The following improvements were noted in the 23-patient cohort: A total of 73.9% (17/23) of patients demonstrated significant tumor shrinkage (>20%); the symptoms of abdominal and back pain were relieved in 15 patients; the survival time was >12 months in 1 patient and >6 months in 14 patients; the patient's general condition, including appetite, was improved in 13 patients; body weight was increased in 9 patients; jaundice was attenuated in 12 patients; and ascites subsided in 10 patients. However, the therapeutic outcome was poor in 2 patients whose tumors size did not show significant change after treatment as detected by CT. These 2 patients succumbed within 6 months. In conclusion, rAd-p53 perfusion via the pancreatic artery is a safe and minimally invasive option for the treatment of mid-late stage pancreatic cancer.

Efficacy of recombinant human adenovirus-p53 combined with chemotherapy for locally advanced cervical cancer: A clinical trial.

The aim of this study was to evaluate the efficacy and safety of recombinant human adenovirus-p53 (rhAd-p53) combined with neoadjuvant chemotherapy in treatment of locally advanced cervical cancer (LACC). A total of 40 patients with LACC (stage IB2 to IIIA) were randomized into 2 groups (n=20 each): PVB group (cisplatin + vincristine + bleomycin, intravenously) and combined group (rhAd-p53 gene therapy + neoadjuvant chemotherapy). Both groups underwent a course of chemotherapy; the only exception was the injection of the rhAd-p53 solution 1×1012 VP intratumorally at an interval of three days thrice in the combined group thereafter. The tumor sizes and adverse events in both groups were observed. The expression of vascular endothelial growth factor (VEGF), protein p53 and micro-vessel density (MVD) in tumor tissue was respectively determined by immunohistochemistry. The evaluation was performed three weeks after the completion of chemotherapy. The efficacy was 75% in the PVB group versus 95% efficacy in the combined group; the tumor size was reduced by 11.42±2.78 cm2 in PVB group versus the significant shrinkage of 15.25±4.00 cm2 in the combined group (P<0.05). The expression of VEGF, p53 and MVD was downregulated in both the PVB and combined groups, with significantly statistical differences versus the control. No additional adverse events were evidenced in the combined group. Therefore, intratumoral injection of rhAd-p53 combined with neoadjuvant chemotherapy has advantage over conventional chemotherapy for its high efficacy, safety and synergism in the therapy for LACC.

Efficacy and safety of recombinant human adenovirus p53 combined with chemoradiotherapy in the treatment of recurrent nasopharyngeal carcinoma.

This study aims to explore the efficacy and safety of recombinant human adenovirus p53 (rAd-p53) combined with chemoradiotherapy (CRT) in the treatment of recurrent nasopharyngeal carcinoma (NPC). A total of 162 recurrent NPC patients were selected and divided randomly into the rAd-p53+CRT, CRT, and rAd-p53 groups. An electrochemical luminescence immune analyzer was used to detect serum levels of tumor markers (carcinoembryonic antigen, cancer antigen 199, and cancer antigen 153). Efficacy evaluation was in accordance with Response Evaluation Criteria in Solid Tumor. Toxicity evaluation was performed according to the WHO grading standard. A 3-year follow-up was performed. A Kaplan-Meier curve was drawn to calculate progression-free survival and the 3-year survival rate. The complete response rate and effective rate (complete response+partial response) of recurrent NPC patients in the rAd-p53+CRT group were higher than those in the CRT and rAd-p53groups. After treatment, compared with the CRT and rAd-p53 groups, the rAd-p53+CRT group had lower serum levels of carcinoembryonic antigen, cancer antigen 199, and cancer antigen 153. The incidences of leukopenia and oral mucositis in the rAd-p53+CRT group were lower than those in the CRT group, but no differences were found between the rAd-p53+CRT and rAd-p53 groups. The progression-free survival and 3-year survival rate of recurrent NPC patients in the rAd-p53+CRT group were higher than the than those in the CRT and rAd-p53 groups. Our study supports that rAd-p53 combined with CRT may provide better efficacy and lower toxicity than rAd-p53 or CRT alone for the treatment of recurrent NPC patients.

Evaluation of efficacy and safety for recombinant human adenovirus-p53 in the control of the malignant pleural effusions via thoracic perfusion.

A certain number of studies have showed that p53 gene transfer has an anti-tumor activity in vitro and in vivo. This study was to evaluate the efficacy and safety of thoracic perfusion of recombinant human adenovirus p53 (rAd-p53, Gendicine) for controlling malignant pleural effusion (MPE). We searched for the relevant studies from the database of MEDLINE, Web of Science, EMBASE, Cochrance Library and CNKI to collect the trials concerning the efficacy and safety of rAd-p53 to treat MPE. Fourteen randomised controlled trials (RCTs) with 879 patients were involved in this analysis. The rAd-p53 combined with chemotherapeutic agents significantly improved the overall response rate (ORR) (P < 0.001; odds ratio = 3.73) and disease control rate (DCR) (P < 0.001; odds ratio = 2.32) of patients with MPE as well as the quality of life (QOL) of patients (P < 0.001; odds ratio = 4.27), compared with that of chemotherapeutic agents alone. In addition, the participation of rAd-p53 did not have an obvious impact on the most of incidence of adverse reactions (AEs) (P < 0.05) except the fever (P < 0.001). However, the fever was self-limited and could be tolerated well. The application of rAd-p53 through thoracic perfusion for treating MPE had a better efficacy and safety, which could be a potential choice for controlling MPE.

Antitumor effects of recombinant human adenovirus-p53 against human cutaneous squamous cell carcinoma in mice.

The present study was conducted to identify the anti-tumor effects of rAd/p53, which is a recombinant human serotype 5 adenovirus, in cutaneous squamous cell carcinoma (cSCC). Mouse models of human cSCC were constructed by injecting human cutaneous squamous cell carcinoma cells into both flanks of nude mice. Subsequently, the 75 nude mice with cSCC xenograft tumors were randomly divided into recombinant human serotype 5 adenovirus (rAd)/p53, rAd/p53 + 5-fluorouracil (5-Fu) and 5-Fu groups. One side of the tumors was administered the therapeutic agents as the therapeutic group, whereas the remaining side was treated with medical saline as the control. At 24, 48, 72, 120 and 168 h post-intratumoral injection, alterations in tumor volume, tumor necrosis and the expression of several tumor-associated genes, including Smad4, Brca1 and matrix metalloproteinase (MMP-2), were analyzed. Compared with its control group, the rAd/P53 group exhibited a significantly increased tumor necrosis ratio. In addition, Smad4 and Brca1 expression levels increased significantly at various time points (P<0.05), and MMP-2 expression decreased significantly (P<0.05). In the rAd/p53 + 5-Fu group, the tumor necrosis ratio, and Smad4 and Brca1 expression levels also significantly increased at various time points (P<0.05). MMP-2 gene transcription gradually decreased, high expression of Smad4 was prolonged, and high expression of Brca1 was observed in the early period following treatment compared with the rAd/P53 group. In addition, p53 expression exhibited a positive correlation with the tumor necrosis ratio and Smad4 expression, and showed a negative correlation with MMP-2 gene transcription (P<0.05). These findings indicate that rAd/p53 has a potent anti-tumor effect in cSCC via the promotion of tumor necrosis and regulating the expression of various tumor-associated genes.

Effects of recombinant human adenovirus-p53 on the regression of hepatic fibrosis.

Hepatic fibrosis is a scarring process that may progress to hepatic cirrhosis and even hepatic carcinoma if left untreated. Hepatic stellate cells (HSCs) play essential roles in the development of hepatic fibrosis. The tumor suppressor protein p53 is a transcription factor that is involved in cell proliferation, cell cycle regulation, apoptosis and DNA repair. Recombinant human adenovirus-p53 (Ad-p53) has been demonstrated to act as a promising antitumor gene therapy in various types of cancer. However, there is limited infomration regarding the therapeutic effect of Ad-p53 on the regression of hepatic fibrosis. In order to examine the underlying molecular mechanism responsible for the effects of Ad-p53 on HSCs, a rat model of hepatic fibrosis was established and HSC-T6 cells were cultured under different conditions. The expression of p53, transforming growth factor (TGF-β1) and α-smooth muscle actin (α-SMA), which is a marker of activated HSCs, was detected by immunohistochemical assays and RT-qPCR. In vitro, five different concentrations (1×106, 5×106, 1×107, 2×107 and 5×107 PFU/ml) of Ad-p53 were selected for use in the MTT assay to analyze the proliferation of HSCs at 0, 24, 48 and 72 h. Flow cytometric analysis was applied to determine the effect of three different concentrations of Ad-p53 (5×106, 1×107 and 2×107 PFU/ml) on the cell cycle and the apoptosis of HSC-T6 cells at 24 and 48 h. The results of immunohistochemical studies and RT-qPCR showed that Ad-p53 upregulated the expression of p53, and downregulated the expression of TGF-β1 and α-SMA. The MTT assay revealed that when treated with various doses of Ad-p53, the proliferation of HSCs was inhibited within a certain range of concentrations and time periods. Analysis of flow cytometric data showed that Ad-p53 arrested the cell cycle in G1 phase and significantly induced apoptosis. Taken together, these findings suggest that Ad-p53 promotes apoptosis and inhibits the proliferation of HSCs in a time- and dose-dependent manner by modulating the expression of p53, TGF-β1 and α-SMA.

Recombinant human adenovirus p53 injection (rAd-p53) is a challenge for anaplastic thyroid cancer treatment.

e17561Background: to evaluate the activity and mechanism of rAd-p53 combined with chemotherapeutics in treatment of ATC in vitro and in vivoand clinical therapies. Methods: p53-mutant ATC cells (C6...

Recombinant human adenovirus p53 injection enhanced sensitivity of chemotherapeutics through DNA damage response pathway in advanced papillary thyroid cancer in vitro and in vivo.

e17560Background: investigate the activity and mechanism of rAd-p53 combined with chemotherapeutics in advanced PTC. Methods: PTC cells (TPC-1) were treated with vehicle, paclitaxel (5 μM), cisplat...

In vitro and in vivo studies on the inhibitory effects of myocardial cell culture medium on growth of a human lung adenocarcinoma cell line, A549.

Although the heart is one of the body's vital organs, with an abundant blood supply, metastasis to the heart is considered rare. In a previous study, we found that the myocardial microenvironment might contain a low molecular weight natural tumour suppressor. The present study was designed to investigate the inhibitory effect of cardiac myocyte-conditioned medium (cmcm) on the growth of A549 human lung adenocarcinoma cells in vitro and in vivo. An mtt assay was used to detect the inhibition ratio with respect to A549 proliferation. Human lung adenocarcinoma cells (A549 cell strain) were transplanted subcutaneously into nude mice to produce tumours. The xenograft tumour growth in mice was observed after selected drug administration. After treatment with cmcm and cisplatin (Cis), A549 cell viability significantly declined (p < 0.001). The cell viability in the cmcm and Cis groups were 53.42% ± 3.45% and 58.45% ± 6.39% respectively. Growth of implanted tumour cells in vivo was significantly inhibited in the cmcm group, the group treated with recombinant human adenovirus-p53, and the Cis-treated group compared with a control group. The inhibition rates were 41.44% in the cmcm group, 41.34% in the p53 group, and 64.50% in the Cis group. Lung metastasis capacity was significantly reduced in the presence of cmcm (p < 0.05). Lung metastasis inhibition rates in mice were 56.52% in the cmcm group, 47.83% in the p53 group, and 82.61% in the Cis group. With cmcm, the lives of A549-tumour-bearing mice could be significantly prolonged without any effect on weight loss. Use of cmcm has the effect of reducing A549 cell viability, tumour volume, and lung metastasis rate, while prolonging survival duration without severe toxicity.

Clinical study of endoscopic intratumor injection of recombinant human adenovirus p53(rAd-p53) combined with esophageal stent implantation in the treatment of advanced esophageal cancer

Objective To compare the efficacy and incidence of complications of stenting alone and intratumoral injection of recombinant human adenovirus p53 combined with stent implantation in the treatment of advanced esophageal cancer patients. Methods 24 cases with advanced esophageal cancer, who could only eat semi liquid, liquid food or could not eat, were randomly divided into control group(A group) and treatment group(B group). 12 cases in A group were treated with esophageal stent implantation,12 cases in B group were given endoscopic intratumor injection of recombinant human adenovirus p53 combined with food tract stent implantation. Results The rate of improvement of dysphasia had no significant difference in survival period: the treatment group survival time of 3.2- 38 months, mean(27.0±2.3)months, while the control group survival time of 2.8- 27months, an average of (14.7±8.0)months,the difference between the two groups was significant(t= 3.521,P< 0.05). The incidence rate of restenosis in treatment group was 8.3%,that in control group was 41.7%. There was significant difference(χ2= 7.532,P<0.05). Conclusion Endoscopic intratumor injection of recombinant human adenovirus p53 combined with esophageal stent implantation in the treatment of advanced esophageal carcinoma can prolong the survival time of patients with esophageal stent implantation, and to reduce the incidence of restenosis. Key words: Esophageal; Neoplasms; Adenoviruses, Human

Efficacy of recombinant adenoviral human p53 gene in the treatment of lung cancer-mediated pleural effusion.

Pleural effusion induced by lung cancer exerts a negative impact on quality of life and prognosis. The aim of the present study was to evaluate the value of the recombinant adenoviral human p53 gene (rAd-p53) in the local treatment of lung cancer and its synergistic effect with chemotherapy. The present study retrospectively recruited 210 patients with lung cancer-mediated pleural effusion who had adopted a treatment strategy of platinum chemotherapy. Pleurodesis was performed via the injection of cisplatin or rAd-p53. Long-term follow-up was conducted to investigate the therapeutic effects of cisplatin and rAd-p53 administration on pleural effusion and other relevant clinical indicators. The short-term effect of pleurodesis was as follows: The efficacy rate of rAd-p53 therapy was significantly higher compared with cisplatin therapy (71.26 vs. 54.47%), and the efficacy of treatment with ≥2×1012 viral particles of rAd-p53 for pleurodesis was significantly greater than treatment with 40 mg cisplatin (P<0.05). Furthermore, efficacy analysis performed 6 and 12 months after pleurodesis indicated that the efficacy rate of rAd-p53 was significantly greater than that of cisplatin (P<0.05). A comparison of median progression-free survival (PFS) time identified a significant difference (P<0.05) between rAd-p53 and cisplatin therapy (3.3 vs. 2.7 months); however, a comparison of median overall survival time identified no significant difference (P>0.05) between rAd-p53 and cisplatin therapy (9.6 vs. 8.7 months). In addition, Cox regression analysis indicated that PFS was not affected by clinical indicators such as age, gender, prognostic staging and smoking status; however, PFS was affected by pathological subtype (adenocarcinoma or squamous carcinoma) in the rAd-p53 group. rAd-p53 administration for pleurodesis exerts long-term therapeutic effects on the local treatment of lung cancer. Thus, a combination of rAd-p53 and chemotherapy may exert a synergistic effect and reverse multidrug resistance.

Ad-p53 enhances the sensitivity of triple-negative breast cancer MDA-MB-468 cells to the EGFR inhibitor gefitinib.

Triple-negative breast cancer (TNBC) accounts for 20% of all molecular subtypes of breast cancer. Neither endocrine nor anti-HER2 molecular targeting treatment yield promising results. At present, epidermal growth factor receptor (EGFR) inhibitor, as a single agent, is unable to obtain encouraging results in the treatment of TNBC, even though most of these tumors overexpress EGFR. In the present study, we used recombinant human p53 adenovirus (Ad-p53) and EGFR inhibitor gefitinib to treat the TNBC cell line MDA-MB-468. The combined treatment of gefitinib and Ad-p53 synergistically inhibited the proliferation of MDA-MB-468 cells; it restrained colony formation, enhanced cellular apoptosis and arrested the cell cycle in vitro, and decreased tumor burden of xenografts in nude mice. Western blot analysis revealed that Ad-p53 and gefitinib in combination significantly downregulated the phosphorylation of protein kinase B (p-Akt) and upregulated caspase-9 and cleaved caspase-3, while there were minimal effects on the expression of extracellular signal-regulated kinase (ERK) and phosphorylation of ERK (p-ERK). These results suggest that Ad-p53 may block the PI3K/Akt pathway rather than the Raf/MEK/ERK pathway. Importantly, wild-type p53 was able to reverse the drug resistance of MDA-MB-468 cells to gefitinib through inactivation of the phosphatidylinositol 3-kinase (PI3K)/Akt pathway. The apoptotic activity induced by this combined treatment may be regulated by caspase cascade-dependent activation.

Effect of recombinant human p53 adenovirus (Ad-p53) combined with EGFR inhibitor gefitinib on the sensitivity of breast cancer MDA-MB-468 cells

To observe the impact of concurrent administration of recombinant human p53 adenovirus (Ad-p53) with EGFR inhibitor gefitinib on breast cancer MDA-MB-468 cells. MDA-MB-468 cells were treated with Ad-p53 and/or gefitinib. The effect of Ad-p53 and gefitinib on the growth of MDA-MB-468 cells was evaluated by MTT assay. Cell apoptosis was detected by flow cytometry. Western blot analysis was used to detect the alteration of p53,EGFR, phosphatidylinositol 3-kinase (PI3K)/Akt signaling pathway and apoptosis-related proteins. Ad-p53 combined with gefitinib was used in vivo to explore their effect on tumor xenograft in nude mice. Immunohistochemistry was used to detect the p53 expression in vivo. The MTT assay showed a stronger inhibitory effect of gefitinib on MDA-MB-468 cells infected with Ad-p53 than on the control cells. Cell apoptosis assay revealed that the apoptosis rates of MDA-MB-468 cells in vehicle-treated group, Ad-p53 group, gefitinib group, and combination group were 8.5%, 17.4%, 20.5% and 32.6%, respectively. The apoptosis rate of MDA-MB-468 cells in the combination group was higher than that in other groups (P < 0.05, for all) . Western blot analysis revealed that the expression of p53 was significantly up-regulated in the presence of Ad-p53. The combination of Ad-p53 and gefitinib significantly down-regulated p-Akt (S473)(P < 0.01) and up-regulated caspase-9 and cleaved caspase-3 (P < 0.01 for both). Tumor inhibition rates (TIR) in the Ad-p53, gefitinib, and combination groups were 35.7%, 28.7% and 74.4%, respectively. Ad-p53 and gefitinib combination therapy significantly reduced the tumor burden in nude mice (P < 0.05 for all).Immunohistochemistry showed that after intratumoral administration of Ad-p53, wild-type p53 was increased (P < 0.01). p53 expressions in the vehicle-treated, Ad-p53, gefitinib and combination groups were 45.2%, 80.1%, 50.7% and 90.6%, respectively. Wild-type p53 may reverse the sensitivity of MDA-MB-468 cells to gefitinib through down-regulation of the PI3K/Akt pathway. The apoptotic activity induced by this combination treatment might be regulated through caspase cascade.