目的 检测96序列相似的家庭成员A(FAM96A)在人肝癌组织中的表达及其与肝癌生物学特征的关系.方法 采用实时荧光定量聚合酶链反应(Real-time PCR)及Western blot法检测FAM96A蛋白在肝癌组织和癌旁组织、HepG2细胞和L02细胞中的mRNA及蛋白表达量,比较其差异,并分析FAM96A蛋白表达差异与肝癌临床病理特征之间的关系.结果 Real-time PCR检测结果显示,FAM96A在肝癌组织中的mRNA表达低于癌旁组织(t=21.773,P＜0.001),在HepG2细胞中的表达低于L02细胞(t=26.153,P ＜0.001).同时,Western blot检测结果证实:与癌旁组织相比,FAM96A在肝癌组织中的蛋白表达显著降低(t=15.582,P＜0.001),在HepG2细胞中的表达同样低于L02细胞(t=14.478,P＜0.001).且FAM96A蛋白表达差异与本研究中48例肝癌患者肿瘤大小、是否合并门静脉癌栓、是否发生肝外转移、Child分级、巴塞罗那肝癌分期之间存在相关性(P＜0.001),然而与患者的性别、年龄、肿瘤个数、是否合并乙肝、是否合并肝硬化、血清甲胎蛋白无明显相关(P＞0.05).结论 FAM96A在人肝癌组织中表达显著下降,其表达水平与肝癌的发生发展、侵袭转移密切相关.

Objective To investigate the expression of family with sequence similarity 96, member B (FAM96B) in 80 cases of gastric cancer and explore the correlation between FAM96B expression and its clinical biological characteristics of gastric cancer. Then to evaluate the proliferation and apoptosis effect of FAM96B overxpression on human gastric carcinoma cell line SGC7901. Methods Western blot was employed to detect FAM96B expression in 80 cases of gastric cancer tissues and its adjacent normal tissues. Furthermore, the correlation between FAM96B expression levels and clinicopathological characteristics of ganstric cancer was analyzed. Moreover, the recombinant plasmid of pcDNA3. l-myc-FAM96B containing the whole sequence of human FAM96B gene was constructed and transfected into SGC7901 cells. MTT essay was used to evaluate the proliferation of transfected cells, and apoptosis was detected by flow cytometry. Results Western blot results showed that FAM96B protein expression levels was significantly higher in the adjacent normal tissues than in gastric cancer tissues (t =25. 218, P＜0. 05). And the FAM96B protein expression was tightly correlated with depth of infiltration, lymph nodes metastasis, distant metastasis and TNM stage (P＜0. 05), but not with gender, age, tumor size. The MTT assay showed that the a value in FAM96B overexpression group was significantly lower than in control group (P＜ 0. 05). FACS analysis indicated that the cell apoptotic rate was increased in FAM96B group than in the control group (t =85. 585, P＜ 0. 05). Conclusion The FAM96B protein expression is significantly decreased in gastric cancer tissues as compared with its adjacent normal tissues. In addition, FAM96B may be a good biomarker to evaluate the development, invasion and metastasis of gastric cancer. Overexpression of FAM96B can inhibit the proliferation and induce the apoptosis of SGC7901 cells.

Objective To investigate the expression of family with sequence similarity 96, member A (FAM96A) in 60 cases of colon cancer tissues and explore the correlation between FAM96A expression differences and clinical biological characteristics of colon cancer,then to evaluate the proliferation and apoptosis effect of FAM96A overx-pression on human colon carcinoma cell line HCT116. Methods Real-time PCR and Western blot were employed to detect FAM96A expression in 60 cases of colon cancer tissues and its adjacent normal tissues. In addition, the correlation between FAM96A expression levels and clinicopathological characteristics of colon cancer was analyzed. Moreover, the recombinant plasmid of pcDNA3. 1-myc-FAM96A containing the whole sequence of human FAM96A gene was constructed and transfected into HCT116 cells. MTT essay was used to evaluate the proliferation of trans-fected cells, and apoptosis was detected by flow cytometry. Results Real-time PCR results confirmed that FAM96A mRNA expression levels was markedly decreased in tumor tissues than that in adjacent normal tissues in the 60 cases colon cancer (t=16. 328, P＜0. 05), in line with qPCR results, Western blot results showed that FAM96A protein expression levels was significantly decreased in colon cancer tissues than in the adjacent normal tissues ( P ＜ 0. 05 ). And the FAM96A protein expression was tightly correlated with depth of infiltration, lymph nodes metastasis, distant metastasis and TNM stage (P＜0. 05), but not with gender, age, tumor size and his- topathological differentiation(P＞0. 05). The MTT assay showed that the A value in FAM96A overexpression group was significantly lower than in control group ( P＜0. 05) . FACS analysis indicated that the cell apoptotic rate was increased in FAM96A group than that in the control group(t=30. 015,P＜0. 05). Conclusion The FAM96A ex-pression is significantly decreased in colon cancer tissues in comparison with its adjacent normal tissues. Addition-ally, FAM96A may be a good marker to evaluate the development, invasion and metastasis of colon cancer. Over-expression of FAM96A can inhibit the proliferation and induce the apoptosis of HCT116 cells.

Objective To investigate the expression of family with sequence similarity 96 member B(FAM96B)in 120 cases of gastric cancer tissues and explore the correlation between FAM96B expression and clinicopathological characteristics of gas-tric cancer and to evaluate the effect of FAM96B overexpression on the proliferation and apoptosis of human gastric carcinoma cell line SGC7901.Methods Western blotting and immunohistochemistry were employed to detect FAM96B expression in 120 cases of gastric cancer tissues and their adjacent normal tissues.The correlation between FAM96B expression levels and clinico-pathological characteristics of gastric cancer was analyzed.Moreover,the recombinant plasmid of pcDNA3.1-myc-FAM96B con-taining the whole sequence of human FAM96B gene was constructed and transfected into SGC7901 cells.MTT assay was used to evaluate the proliferation of transfected cells,and flow cytometry to detect cell apoptosis.Results Immunohistochemistry showed that FAM96B protein was located in the cytoplasm of SGC7901 cell.In addition,thepositive expression rate of FAM96B in tumor-adjacent tissues and gastric cancer tissues was 62.5%(75/120)and 20.8%(25/120),respectively,with the difference being statistically significant(χ2=45.067,P<0.05).Western blot results showed that the expression levels of FAM96B pro-tein were significantly higher in the adjacent normal tissues than in gastric cancer tissues[(1.54 ± 0.48)vs.(0.53 ± 0.20),t=10.395,P<0.05)].The FAM96B protein expression was tightly correlated with the depth of infiltration,lymph nodes metasta-sis,distant metastasis and TNM stage(P<0.05),but not with gender,age,tumor size,differentiation or histologic subtype(P>0.05).The MTT assay showed that the A value in FAM96B overexpression group was significantly lower than in control group (P<0.05).FACS analysis indicated that the cell apoptotic rate was much higher in FAM96B group than in the control group [(49.5 ± 1.03)% vs.(6.7 ± 0.81)%,P< 0.05].Conclusion The FAM96B expression is significantly decreased in gastric cancer tissues as compared with the adjacent normal tissues.The expression of FAM96B is related to the development,invasion and metastasis of gastric cancer.Overexpression of FAM96B can inhibit the proliferation and induce the apoptosis of gastric cancer cells.

Objective To investigate the expression of family with sequence similarity 96 member A(FAM96A)in the liver cancer tissues and to evaluate its effects on the cell proliferation and apoptosis of human liver cancer cells HepG2. Methods Real-time PCR and Western blotting were applied to detect the mRNA and protein expression levels of FAM96A in the liver cancer tissues and their adjacent tissues,HepG2 cells and L02 cells. Furthermore,the recombinant plasmid of pcDNA3. 1-myc-FAM96A containing the whole sequence of human FAM96A gene (FAM96A group)and pcDNA3. 1-vector pcDNA3. 1-vector blank plasmid (control group)were respectively transfected into HepG2 cells. Then MTT essay and flow cytometry were applied to detect the proliferation and apoptosis rate of HepG2 cells in the two groups. Results FAM96A mRNA levels were significantly decreased in the liver tissues than in the adjacent tissues (0. 704 ± 0. 178 vs. 1. 707 ± 0. 267)and in HepG2 cells than in L02 cells (0. 627 ± 0. 251 vs. 1. 654 ± 0. 285),(both P < 0. 05). While FAM96A protein expression levels were lower in the liver tissues as compared with those of the adjacent tissues and were lower in HepG2 cells than in L02 cells (both P < 0. 05). Moreover,MTT assay showed that the proliferation of the FAM96A group was significantly lower than that of the control group (P < 0. 05). FACS analysis indicated that the apoptotic rate was high-er in the FAM96A group than in the control group (33. 06% ± 3. 15% vs. 5. 08% ± 0. 75%),(P < 0. 05). Conclusion The fusion protein SMP30-IP10 eukaryotic expression plasmid is successfully con-structed,and it can inhibit the migration and invasion abilitiesof hepatoma cells,but has no effect on the cell proliferation.

Objective To investigate the function of family with sequence similarity 96,member B (FAM96B) in apoptin-induced apoptosis in a hepatoma carcinoma cell line HepG2.Methods The recombinant plasmid of pcDNA3.1-myc-FAM96B encoding the human FAM96B gene and pcDNA3-HA-apoptin encoding the human apoptin gene were co-transfected into HepG2 cells.Then laser scanning confocal microscopy was used to observe the celluar localization.The HepG2 cells apoptosis induced by FAM96B and apoptin was detected by flow cytometry.Results The observed results by laser scanning confocal microscopy showed that apoptin was located in the nucleus of the HepG2 cells,while FAM96B in the cytoplasm.FAM96B overexpression resulted in partial apoptin retention in the cytoplasm.Moreover,flow cytometry analysis showed that the apoptosis rate of HepG2 cells in apoptin group was decreased from (44.85 ± 1.85) ％ to (31.76 ± 1.88) ％ (P ＜ 0.05) in apoptin and FAM96B co-transfection group,indicating that FAM96B interacting with apoptin markedly decreased the apoptosis rate of HepG2 cells induced by apoptin.Conclusion The data revealed that when FAM96B and apoptin were co-transfected into HepG2 cells,FAM96B overexpression reulted in partial distribution of apoptin in the cytoplasm,which significantly inhibited the apoptosis rate of the HepG2 cells induced by apoptin.

目的 观察96序列相似的家庭成员B(family with sequence similarity 96,member B,FAM96B)在56例结肠癌组织中的表达,并探讨其对结肠癌细胞系HCT-116细胞增殖及凋亡的影响.方法 分别采用实时荧光定量PCR(real-time PCR)及Western blot检测56例结肠癌肿瘤组织和癌旁组织中FAM96B的mRNA及蛋白表达水平.构建含人FAM96B全长序列的pcDNA3.1-myc-FAM96B重组质粒,并通过脂质体质粒转染人结肠癌细胞系HCT-116细胞,采用噻唑蓝(MTT)法检测FAM96B过表达对HCT-116增殖能力的影响,采用流式细胞技术检测其对细胞周期和凋亡的影响.结果 在56例结肠癌组织中,FAM96B mRNA在肿瘤组织中的表达显著低于癌旁组织(P＜0.05).FAM96B蛋白在肿瘤组织中的表达同样低于癌旁组织(P＜0.05).MTT细胞实验结果表明FAM96B组吸光度(A)值显著低于对照组(P＜0.05),即过表达FAM96B可抑制HCT-116细胞增殖.流式细胞仪检测结果显示过表达FAM96B组的细胞凋亡率高于对照组[(44.70±1.12)％ vs.(4.30±0.91)％,P＜0.05).细胞周期分析显示,过表达FAM96B组在G1期的细胞百分数[(51.58±0.97)％]显著低于对照组[(62.64±0.87)％,P＜0.05],S期的细胞百分数[(35.35±0.58)％]显著高于对照组[(25.79±0.74)％,P＜0.05].结论 FAM96B在结肠癌组织中低表达,过表达FAM96B可抑制结肠癌细胞系HCT-116增殖且诱导其凋亡.FAM96B可能作为一个潜在抑癌基因直接参与结肠癌发生、发展过程,并有可能成为结肠癌新的抗癌靶点.

Objective To investigate the expression difference of family with sequence similarity 96,member B (FAM96B) in 86 cases of colon cancer tissues and explore the clinical significance.Methods Eighty-six cases of colon cancer tissues and their adjacent tissues were collected from January 2014 to March 2015 in our hospital.Real-time quantitative polymerase chain reaction (Real-time PCR),Western blotting and immunohistochemistry were used to examine the expression and distribution of FAM96B in colon cancer tissues and their adjacent tissues from 86 patients with colon cancer.Further more,the correlation between the expression difference of FAM96B and clinicopathological characteristics of colon cancer was analyzed.Results In 86 patients with colon cancer,FAM96B mRNA levels were significantly higher in tumor tissues than in adjacent tissues (1.54 ± 0.20 vs.0.63 ± 0.10,P ＜ 0.05).The FAM96B protein expression levels in tumor tissues were lower than in adjacent tissues (P ＜ 0.05).The expression difference was correlated with lymph nodes metastasis,distant metastasis and TNM stage (P ＜ 0.05),but not with gender,age,tumor size,differentiation or histologic subtype (P ＞ 0.05).Immunohistochemistry showed that FAM96B protein was located in cytoplasm.In addition,the positive expression rate of FAM96B in tumor tissues and adjacent tissues was 77.9％ (67/86) and 29.1％ (25/86) respectively (P ＜ 0.05).Conclusion Our data demonstrate that the expression of FAM96B in colon cancer tissues is significantly decreased as compared with that in adjacent tissues.The expression difference was correlated with lymph nodes metastasis,distant metastasis and TNM stage.Additionally,FAM96B may be a good marker to evaluate the invasion and metastasis.

Worldwide, cervix carcinoma is among the most dangerous cancer types, and novel therapies are under development. Cancer treatments are often hampered because of lack of specificity. The chicken anemia virus-derived apoptin induces apoptosis selectively in tumor cells and leaves normal cells unharmed. Here, we have carried out in-vitro and in-vivo studies on the cytotoxic effect of apoptin in a cervix carcinoma model. Apoptin was fused to the protein transduction domain 4 (PTD4), enabling delivery of the fusion protein across cellular membranes. PTD4-apoptin protein is located in the nuclei of human cervical carcinoma HeLa cells and in the cytoplasm of normal cells L02. By MTT and flow cytometry analysis, we have proven that PTD4-apoptin protein induced apoptosis in the cervical carcinoma cells. PTD4-apoptin enhanced the level of active executioner caspase-3. Neither caspase-3 activation nor apoptin-induced accumulation of the mitochondrial outer-membrane protein Mfn-2 was affected by ectopic Bcl-2 expression. In contrast, apoptin-mediated AKT activation was inhibited by Bcl-2. In vivo, cervix carcinoma xenografts were treated for 7 days with PTD4-apoptin protein. The PTD4-apoptin treatment induced a decrease in the cervix carcinoma, whereas the PTD4-GFP protein-treated controls expanded significantly. TUNEL analysis showed that PTD4-apoptin protein induced apoptosis in cervix carcinoma cells, in contrast to the control PTD-GFP-treated ones. Our results indicate that apoptin is a potential anticancer agent for treating cervix carcinoma.

Gambogic acid (GA), the main active component of gamboge resin, has potent antitumor activity both in vivo and in vitro. However, the underlying molecular mechanisms remain unclear. In this study, we found that GA could initiate autophagy in colorectal cancer cells, and inhibition of the autophagy process accelerated the effect of proliferative inhibition and apoptotic cell death induced by GA, implying a protective role of autophagy. Two-dimensional electrophoresis-based proteomics showed that GA treatment altered the expression of multiple proteins involved in redox signaling and lipid metabolism. Functional studies revealed that GA-induced dysregulation of lipid metabolism could activate 5-lipoxygenase (5-LOX), resulting in intracellular ROS accumulation, followed by inhibition of Akt-mTOR signaling and autophagy initiation. Finally, results using a xenograft model suggested ROS-induced autophagy protect against the antitumor effect of GA. Taken together, these data showed new biological activities of GA against colorectal cancer underlying the protective role of ROS-induced autophagy. This study will provide valuable insights for future studies regarding the anticancer mechanisms of GA.

Deletion of the short arm of chromosome 3 is one of the most frequent genetic alterations in many solid tumors including nasopharyngeal carcinoma (NPC), suggesting the existence of one or more tumor suppressor genes (TSGs) within the frequently deleted region. A putative TSG RBMS3 (RNA binding motif, single stranded interacting protein 3), located at 3p24-p23, has been identified in our previous study. Here, we reported that downregulation of RBMS3 was detected in 3/3 NPC cell lines and 13/15 (86.7%) primary NPC tissues. Functional studies using both overexpression and suppression systems demonstrated that RBMS3 has a strong tumor suppressive role in NPC. The tumor suppressive mechanism of RBMS3 was associated with its role in cell cycle arrest at the G1/S checkpoint by upregulating p53 and p21, downregulating cyclin E and CDK2, and the subsequent inhibition of Rb-ser780. Further analysis demonstrated that RBMS3 had a pro-apoptotic role in a mitochondrial-dependent manner via activation of caspase-9 and PARP. Finally, RBMS3 inhibited microvessel formation, which may be mediated by down-regulation of MMP2 and β-catenin and inactivation of its downstream targets, including cyclin-D1, c-Myc, MMP7, and MMP9. Taken together, our findings define a function for RBMS3 as an important tumor suppressor gene in NPC.

A disintegrin and metalloproteinase 10 (ADAM10) was identified as a key protease in the ectodomain shedding of various substrates, such as Notch1 protein, ErbB2 and E-cadherin, which are important in the development of non-small cell lung cancer (NSCLC). The aim of this study was to investi-gate the role of ADAM10 in NSCLC metastasis.We characterized the expression of ADAM10 and Notch1 in human NSCLC tissues in vivo. Immunohistochemical analysis indicated that ADAM10 expression was significantly increased in the NSCLC tissues, particularly in the metastatic tissues. Futhermore, ADAM10 overexpression positively correlated with Notch1 expression in the NSCLC tissues. The in vitro downregulation of ADAM10 expression using ADAM10 short hairpin RNA (shRNA) reduced the migration and invasion of NSCLC cells. We present further evidence that ADAM10 promotes NSCLC cell migration and invasion via the activation of the Notch1 signaling pathway. Taken together, our results suggest that ADAM10 may serve as a potential target for the therapeutic intervention of NSCLC metastasis. The data provided in this study may aid in the further understanding of the function of ADAM10 in the progression of NSCLC and open new perspectives for the diagnosis and treatment of NSCLC.

BACKGROUND: Very low density lipoprotein receptor is regarded as a Swiss Army Knife receptor, and many researchers have studied this receptor. But there are only several kinds of commercial antibodies and the price is on the high side. OBJECTIVE: To get the monoclonal antibody against the c-terminal of very low density lipoprotein receptor for the future study. METHODS: In order to obtain the very low density lipoprotein receptor, hybridoma IgG 6A6 cel s related with very low density lipoprotein receptor intracel ular domain was injected into peritoneal of Balb/c mice. After 2 weeks, ascites was col ected, and the target protein was preliminary purified by salting-out method (n-octanoic acid-saturated ammonium sulfate precipitation method) and further purified by affinity chromatography, and the monoclonal antibody related with very low density lipoprotein receptor intracel ular domain was obtained. The relative molecular mass and purity were detected by sodium dodecyl sulfate polyacrylamide gel electrophoresis, and the activity was detected by enzyme-linked immunosorbent assay. RESULTS AND CONCLUSION: Western Blotting results showed that the antibody from the ascites directly can bind the very low density lipoprotein receptor protein, but the background was not clear. The purified antibody from the ascites through salting-out method (n-octanoic acid-saturated ammonium sulfate precipitation method) and then by protein A affinity chromatography can bind specifical y with the very low density lipoprotein receptor. The pure and activity monoclonal antibodies can be obtained through purification by the salting-out method and Protein A Agarose.

Very low density lipoprotein receptors (VLDLR) including type I and type II are known to affect cell functions by binding to its extracellular ligands. However, the effect of these ligands on VLDLR expression remains elusive. Tissue factor pathway inhibitor (TFPI) and urokinase plasminogen activator and plasminogen activator inhibitor 1 (uPA-PAI-1) complex, two ligands of VLDLR, were used to examine their effects on VLDLR expression. TFPI treatment decreased type II VLDLR expression, inhibited cell proliferation and migration, and degradated beta-catenin in SGC7901 cells. However, uPA-PAI-1 complex, increased type II VLDLR expression with promoted cell proliferation and migration and stabilization of beta-catenin. These results indicated that extracellular ligands can change the expression of type II VLDLR to affect cell proliferation and migration.

Background and Aim:  Chinese traditional medical science is generally used as a therapeutic method against functional dyspepsia (FD) in China. Although great effort is made to understand the pharmaceutical mechanisms of Chinese traditional medicine, such as typical traditional Chinese medicine, Wei Kangning, there are still many mysteries to be uncovered.

Objective Using proteomics to explore the phasic expression profiles of proteins in rat during foreign nerve regeneration after somatic-autonomic nerve anastomosis. Methods The artificial somatic-autonomic nerve anatomosis were established in rats. Foreign nerves and contralateral somatic nerves were collected at 7,14 and 28 days respectively after operation. Extracts of foreign nerves were analyzed by two-dimensional gel eletrophoresis and the differential proteins were measured by matrix asisisted laser desorption ionization time of flight mass spectrometry. The data obtained from peptide mass fingerprinting (PMF) were used in protein database search and the protein identification. Results Mass spectrometric analysis identified 25 proteins displayed different function,including proteins in myeline sheath,inflammatory factors at acute stage,nerve cell cytoskeletal proteins and lipid metabolism proteins etc. The differential proteins may play a part at the process of Wallerian degeneration,axon regeneration and remyelinization.Conclusion Through proteome study we acquired time sequence protein expressions of regenerated foreign nerve,and successfully identified 25 proteins correlated with the process of foreign nerve regeneration. These results suggest that Schwann cells and macrophage cells may play important roles in the process of the foreign nerve regeneration.

Reported data indicate that cholesterol loading in the liver can cause hepatic injury. To explore the possible mechanisms of cell damage resulting from cholesterol overloading in hepatocytes, cell apoptosis, the unfolded protein response (UPR) and the correlation between them were assessed in the cholesterol-overloaded normal human hepatic cell line L02. L02 cells were incubated with 200 microg/ ml of low density lipoprotein (LDL) for 24 h with or without 20 microg/ml 58035, an inhibitor of acyl-CoA:cholesterol acyltransferase (ACAT). In the LDL+58035 group, the intracellular cholesterol level was dramatically increased, which was measured by an enzymatic combined high performance liquid chromatography assay. Expression of immunoglobulin-binding protein, X-box binding protein 1, activating transcription factor 6, activating transcription factor 4, CCAAT/enhancer-binding protein homologous protein-10, markers of endoplasmic reticulum stress (ERS)/ UPR, were up-regulated as determined using reverse transcription-polymerase chain reaction (RT-PCR) or Western blot analysis. The rate of cell apoptic death increased 21.3+/-2.4%. Meanwhile, the active caspase-3 protein expression was increased 8.4-fold compared to the active caspase-3 protein expression in the controls. Furthermore, 4-phenylbutyric acid, an inhibitor of UPR, partly reduced cell apoptosis and activation of caspase-3. This study suggests that cholesterol overloading in hepatic L02 cells induces ERS and activates the UPR which, in part, leads to the apoptotic damage of cells.

In hypertriglyceridaemic individuals, atherosclerogenesis is associated with the increased concentrations of very low density lipoprotein (VLDL) and VLDL-associated remnant particles. In vitro studies have suggested that VLDL induces foam cells formation. To reveal the changes of the proteins expression in the process of foam cells formation induced by VLDL, we performed a proteomic analysis of the foam cells based on the stimulation of differentiated THP-1 cells with VLDL. Using two-dimensional gel electrophoresis (2-DE) and matrix-assisted laser-desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS) analysis, 14 differentially expressed proteins, containing 8 up-regulated proteins and 6 down-regulated proteins were identified. The proteins are involved in energy metabolism, oxidative stress, cell growth, differentiation and apoptosis, such as adipose differentiation-related protein (ADRP), enolase, S100A11, heat shock protein 27 and so on. In addition, the expression of some selected proteins was confirmed by Western blot and RT-PCR analysis. The results suggest that VLDL not only induces lipid accumulation, but also brings about foam cells diverse characteristics by altering the expression of various proteins.

Apoptin protein harbors tumor‐selective cell death activity, which makes it a potential anticancer therapy candidate. This study reports an apoptin therapy approach based on protein transduction domain 4 (PTD4)‐mediated transduction of recombinant apoptin protein. In vitro , the PTD4‐apoptin fusion protein is located in the nucleus and induces cell death in, e.g ., human hepatocarcinoma HepG2 cells. In normal human L‐02 hepatocytes, PTD4‐apoptin protein retained mainly cytoplasmic and did not induce detectable levels of cell death, illustrating that the PTD4 domain does not affect apoptin's tumor‐selective characteristics. In vivo , liver, cervix and gastric carcinoma xenografts treated with PTD4‐apoptin protein for 6 days via the tumor epidermis exhibited a significant tumor growth inhibition because of apoptin‐mediated cell death. In addition, treatment of human hepatocarcinoma xenografts during 3 weeks showed that PTD4‐apoptin protein has significant anticancer activity, whereas control treatment with PTD4‐enhanced green fluorescence protein or saline did not. Cell death and disruption of the tumor integrity were apparent in the PTD4‐apoptin transduced xenografted tumors. As important, although PTD4‐apoptin protein could be detected in the epidermal tissue covering the subcutaneous tumor tissue and in several organs, such as liver and brain, of the treated mice, no tissue disruption or signs of cell death could be detected. Our in vivo data reveal that apoptin protein delivery constitutes a novel powerful and safe anticancer therapy. © 2009 UICC