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Background Interleukin-6 receptor antibody (IL6R) inhibits colony formation and invasion by colorectal carcinoma (CRC) in vitro. We examined the effect of IL6R antibody on tumor growth of CRC xenografts in vivo. Materials and methods SW480 cells inoculated subcutaneously into NU/NU mice were treated with anti-IL6R and tumor histology and growth-related signaling were subsequently estimated by hematoxylin and eosin and immunohistochemical staining. Results Tumor growth was inhibited by anti-IL6R treatment at dosages of both 0.1 and 1.0 mg/kg. Tumor cells had invaded into surrounding tissues in untreated mice, while there was no invasion of tumors in the IL6R antibody-treated mice. The expression of Ki-67, signal transducer and activator of transcription protein 3 (STAT3) and phosphor-extracellular signal-regulated kinase 1 and 2 (ERK1/2) were suppressed in anti-IL6R-treated tumors. Conclusion IL6R antibody inhibited tumor growth and invasiveness in vivo by suppressing the expression of Ki-67, STAT3 and phosphor-ERK1/2. The results imply that the anti-IL6R may be a promising targeted drug for CRC.

Background Immunotherapy is an emerging cancer therapy with potential great success; however, immune checkpoint inhibitor (e.g., anti-PD-1) has response rates of only 10–30% in solid tumor because of the immunosuppressive tumor microenvironment (TME). This affliction can be solved by vascular normalization and TME reprogramming. Methods By using the single-cell RNA sequencing (scRNAseq) approach, we tried to find out the reprogramming mechanism that the Fc-VEGF chimeric antibody drug (Fc-VFD) enhances immune cell infiltration in the TME. Results In this work, we showed that Fc-VEGF121-VEGF165 (Fc-VEGF chimeric antibody drug, Fc-VFD) arrests excess angiogenesis and tumor growth through vascular normalization using in vitro and in vivo studies. The results confirmed that the treatment of Fc-VFD increases immune cell infiltration including cytotoxic T, NK, and M1-macrophages cells. Indeed, Fc-VFD inhibits Lon-induced M2 macrophages polarization that induces angiogenesis. Furthermore, Fc-VFD inhibits the secretion of VEGF-A, IL-6, TGF-β, or IL-10 from endothelial, cancer cells, and M2 macrophage, which reprograms immunosuppressive TME. Importantly, Fc-VFD enhances the synergistic effect on the combination immunotherapy with anti-PD-L1 in vivo. Conclusions In short, Fc-VFD fusion normalizes intratumor vasculature to reprogram the immunosuppressive TME and enhance cancer immunotherapy.

To investigate the influence of longan flower extract (LFE) on the sensitization of colorectal cancer (CRC) cells to 5-fluorouracil (5-FU) treatment, HT-29, Colo 320DM and SW480 cells were treated with LFE and 5-FU alone and in combination, and the cell viability was then assessed by trypan blue exclusion, the cell cycle by propidium iodide staining, the mitochondria membrane potential by rhodamine 123 staining, and the expression levels of associated genes by immunoblotting and quantitative real-time polymerase chain reaction. LFE and 5-FU synergistically inhibited cell proliferation of HT-29 and Colo 320DM cells. Combined treatment also elevated the level of loss of mitochondria membrane potential of these two CRC cells and arrested HT-29 cells in the S phase of the cell cycle, in association with down-regulation of cyclin A mRNA expression. LFE synergistically potentiated chemosensitivity to 5-FU in at least two CRC cell lines. The results indicated that LFE has potential as a novel agent for the sensitization of CRC cells to 5-FU.

Aim of Study: Proanthocyanidin-rich longan flower extract (LFP) has been previously shown to inhibit the proliferation and anchorage-independent growth in soft agar of two colorectal carcinoma (CRC) cells in vitro. In this report, we further examined the effects of LFP in a CRC spheroid model. Materials and Methods: A liquid-overlay assay employing HT-29 spheroids was used to evaluate the effects of LFP on cancer cell tumorigenesis, viability, and apoptosis. Associated effects on signaling path ways (epidermal growth factor receptor [EGFR], Akt) and apoptotic regulators were measured using Western blot. Results: Treatment with LFP up to 200 μg/ml inhibited tumor growth in a dose-dependent manner and induced prominent apoptosis as measured by annexin V staining. Cells treated with LFP showed decreased EGFR and Akt phosphorylation with decreased expression of B-cell lymphoma 2. Conclusion: The ability of LFP to induce apoptosis in CRC spheroids warrants further investigation of its composition and identification of tumor-active components.

Objectives The study is aim at evaluating the effects of GABA tea on colorectal cancer cell proliferation colony formation and invasion Methods Colorectal cancer cell line HT treated with GABA tea extract mg mL were assessed for viability by MTT assay and for their invasion potential by evaluating their ability to penetrate through a matrix gel coated Boyden chamber Results GABA tea extract exhibited slight effect on cell proliferation of HT The colony formation was inhibited in both culture plate and Boyden chamber Conclusions GABA tea extract inhibited the colony formation and invasion of colorectal cancer cells GABA tea is a potential adjuvant agent for colorectal cancer therapy

Background Litchi seeds possess rich amounts of phenolics and have been shown to inhibit proliferation of several types of cancer cells. However, the suppression of EGFR signaling in non-small cell lung cancer (NSCLC) by litchi seed extract (LCSE) has not been fully understood. Methods In this study, the effects of LCSE on EGFR signaling, cell proliferation, the cell cycle and apoptosis in A549 adenocarcinoma cells and NCI- H661 large-cell carcinoma cells were examined. Results The results demonstrated that LCSE potently reduced the number of cancer cells and induced growth inhibition, cell-cycle arrest in the G1 or G2/M phase, and apoptotic death in the cellular experiment. Only low cytotoxicity effect was noted in normal lung MRC-5 cells. LCSE also suppressed cyclins and Bcl-2 and elevated Kip1/p27, Bax and caspase 8, 9 and 3 activities, which are closely associated with the downregulation of EGFR and its downstream Akt and Erk-1/-2 signaling. Conclusion The results implied that LCSE suppressed EGFR signaling and inhibited NSCLC cell growth. This study provided in vitro evidence that LCSE could serve as a potential agent for the adjuvant treatment of NSCLC.

Grape-seed procyanidins (GSPs) can inhibit cell proliferation and invasiveness in various human cancers. However, the effect of GSP on pancreatic carcinoma cells has not been investigated.Pancreatic carcinoma cell lines MIA PaCa-2 and BxPC-3 treated with GSP were assessed for viability by trypan blue exclusion, for cell cycle distribution by flow cytometry, for increased apoptosis by annexin V labeling, for their adhesion and invasion potential by evaluating their ability to penetrate through a matrix gel-coated Boyden chamber, and for changes in the levels of proteins involved in cellular events by immunoblotting.Grape-seed procyanidin inhibited MIA PaCa-2 and BxPC-3 proliferation in a dose-dependent manner and induced G1-phase arrest of the cell cycle in BxPC-3 or mitochondria-mediated apoptosis in MIA PaCa-2. Grape-seed procyanidin also inhibited the adhesion and invasion potential of both cell lines in a dose-dependent manner, which are associated with the suppression of metalloproteases matrix metalloproteinase 9 or 2 (MMP-9 or -2) expression.Grape-seed procyanidin inhibited the proliferation of pancreatic carcinoma cells by cell cycle blockage or apoptotic induction. The invasiveness was also suppressed by GSP through down-regulation of MMP-2 or MMP-9 in pancreatic carcinoma cells. Grape-seed procyanidin is a potential chemotherapeutic or preventive agent for pancreatic carcinoma.

Pinolenic acid (PNA), a naturally-occurring polyunsaturated fatty acid (PUFA), is found mainly in pine seeds. Although many studies have demonstrated beneficial effects of pine seed oil, there are no reports of the biological effects of PNA on cancer metastasis. The objective of this study was to investigate the effect of PNA on human breast cancer MDA-MB-231 cell proliferation and metastasis in vitro . We found that PNA did not affect cell viability and cell-matrix adhesion, but it inhibited cell metastasis by suppressing cell invasiveness and motility. Suppression could in part be associated with the modification of the n −6 PUFA composition of cells by PNA which significantly decreased the percentage of arachidonic acid (AA) in phospholipids from 12.6% to 4.9%. The lower AA content of the cancer cells might result in less synthesis of prostaglandin E 2 (PGE 2 ), and subsequent down-regulation of inducible cyclooxygenase (COX-2) expression. Thus, PNA represents a potential anti-cancer agent.

Eur J Clin Invest 2011; 41 (3): 277–284 Abstract Background Interleukin-6 (IL-6) promotes proliferation and invasion in colorectal carcinoma, and serum IL-6 levels are correlated with survival in patients with colorectal carcinoma. In this study, we attempted to clarify the signal pathway downstream of IL-6 and the role of the IL-6 receptor complex in terms of the biological effects of clonogenic growth and invasiveness in colorectal carcinoma cells. Materials and methods IL-6-stimulated SW480 cells were treated with IL-6 receptor neutralization antibody, mitogen-activated protein kinase (MAPK) inhibitor and phosphatidylinositol 3-kinase inhibitor, and clonogenic growth and invasiveness were assessed. IL-6 and IL-6 receptor-expressing LoVo cells were also tested the IL-6 receptor antibody effect. The downstream molecules of the IL-6-mediated pathway were also evaluated. Results IL-6 effectively enhanced the clonogenicity and invasiveness of SW480; however, these abilities were reversed by treatment with anti-IL-6 receptor antibody, and MAPK and PI3K inhibitors exhibited partial ability to reduce these effects. Similar effects were also found in anti-IL-6 receptor antibody-treated LoVo cells in addition of modulating STAT3 pathway. Anti-IL-6 receptor antibody also inhibited matrix metalloproteinase-2 (MMP-2) and 9 (MMP-9) expressions in IL-6-stimulated SW480. Conclusions IL-6 and the IL-6R complex could induce clonogenic growth and invasiveness by mediating signals in the Ras/MAPK and PI3K/AKt pathways, and the malignant phenotypes might be associated with the production of MMP-2 and MMP-9 after IL-6 stimulation in SW480 cancer cells.

Longan flower extract (LFE) has been shown to exhibit free radical scavenging ability and anti-inflammatory effects. However, the effect of LFE treatment on the growth of colorectal cancer cells has not been evaluated. This study investigated the effect of LFE on two colorectal cancer cell lines, SW-480 and Colo 320DM, and the possible mechanisms involved. LFE-treated cells were assessed for viability by trypan blue exclusion, for in vitro tumorigenesis by seeding cells in soft agar to allow anchorage independent growth, for cell cycle distribution by flow cytometry, for loss of mitochondrial membrane potential by rhodamine 123 staining, for increased apoptosis by DNA fragmentation assay, and for changes in the levels of proteins involved in cell cycle control and apoptosis by immunoblotting. LFE (25-400 microg/ml) could inhibit proliferation in a dose- and time-dependent manner. The cell cycle of both LFE-treated cell lines showed obvious S phase block. Western blotting further showed the S phase block in these two cell lines was mainly due to cyclin E accumulation and cyclin A decrease. LFE treatment increased rhodamine 123-negative cells and DNA fragmentation in Colo 320DM cells but not in SW480 cells. Increased levels of the apoptosis activation protein, caspase 3, were also found in Colo 320DM cells. The activation of caspase 3 in LFE-treated SW480 cells was not significant. The caspase 3 activation in Colo 320DM cells by LFE was mediated by the suppression of Bcl-2 protein levels. LFE treatment could inhibit the proliferation and malignancy of colorectal cancer cell lines and was associated with S phase block of the cell cycle. An apoptotic mechanism induced by LFE involving a loss of mitochondrial membrane potential and caspase 3 activation was found in Colo 320DM cells but not in SW480 cells. The results of this study indicate that LFE has potential to be developed as a novel functional food or chemopreventive agent for colorectal cancer.

Hypotheses. Epithelial-mesenchymal transition (EMT) and invasion play a critical role in cancer progression and metastasis. We have shown that low E-cadherin and high Twist expression are significantly correlated with prognostic survival prediction in oral squamous cell carcinoma (OSCC). This study aimed to determine the anti-invasive effect of curcumin on the expression of matrix metalloproteinases (MMPs) and of EMT regulators in OSCC. Methods. SCC-25 cells were treated with curcumin, and cell proliferation, invasion, and expression of MMPs and EMT regulators were assessed for cell viability by trypan blue exclusion, for invasion by Matrigel invasion chamber, and for EMT regulators and MMP changes in the levels of proteins by immunoblotting. Results. Our data showed that curcumin treatment not only decreased the expression of MMP-2 and MMP-9 to inhibit invasiveness in oral cancer but also modulated the expression of EMT markers, such as Snail, Twist, and E-cadherin, and induced p53 expression that is crucial to EMT repression. Conclusion. Curcumin has the potential to become an adjunctive regimen for the prevention of cancer progression and metastasis in oral cancer.

BACKGROUND. Previously, the authors reported that specific antisense suppression of overexpressed proline-directed protein kinase (PDPK) F A enhances the chemosensitivity of various clinical anticancer drugs up to > 100-fold in human prostate carcinoma cells, suggesting an association of PDPK F A with drug resistance in human malignancies. METHODS. In this report, by using a similar approach, the authors demonstrate further that the suppression of PDPK F A enhances even more dramatically the chemosensitivity of clinically used anticancer drugs in various types of human acute lymphoblastic leukemia (ALL) cells. RESULTS. Compared with parental and control transfected cells, transduced ALL cells (both lurkat and CCRF-CEM cells) with low levels of PDPK F A displayed an enhanced sensitivity to vincristine, vinblastine, paclitaxel, methotrexate, doxorubicin, and daunorubicin. Estimation of the 50% inhibitory concentration (IC 50 ) index further revealed that the transduced cells displayed up to > 3000-fold drug sensitivity, and there was a correlation between suppressed levels of PDPK F A and drug sensitivity. A mechanistic study further revealed that the enhanced chemosensitivity in transduced ALL cells was due mainly to the potentiation of apoptotic induction. CONCLUSIONS. Taken together, the results demonstrate that the suppression of overexpressed PDPK F A greatly enhances the chemosensitivity of various clinical anticancer drugs in both types of human ALL cells, providing initial evidence for an important role of this PDPK in controlling multidrug resistance of ALL.

BACKGROUND Initial clinic studies revealed that the overexpression of proline-directed protein kinase FA (PDPK FA) is associated conversely with various stages of tumor tissue differentiation. However, the role of overexpressed PDPK FA in tumor cell differentiation remains unknown and needs to be established. In this report, the authors explore the potential role of PDPK FA in cellular differentiation by investigating the effects of partial inhibition of this kinase on erythroid differentiation of chronic myeloid leukemia cells (K562). METHODS PDPK FA antisense expression vector and its specific antibody were developed successfully. Two stable, transfected antisense clones of human myeloid leukemia cells were subcloned that expressed ≈80% and ≈50% of the total PDPK FA existing in control-transfected clones, as determined by both immunoprecipitate activity assay and immunoblot analysis. In sharp contrast, the PDPK FA antisense clones expressed no significant suppression of any other related PDPK members' expression, demonstrating the specificity of these two antisense clones. RESULTS The antisense clones proportionally induced spontaneous erythroid differentiation up to ≈30% of the total K562 cells. Moreover, antisense suppression of PDPK FA expression appeared to potentiate sodium butyrate/hemin-induced erythroid differentiation of K562 cells to a more complete stage compared with the control. CONCLUSIONS The results demonstrate that specific antisense suppression of overexpressed PDPK FA in human myeloid leukemia cells is sufficient to potentiate both spontaneous and drug-induced erythroid differentiation, indicating that PDPK FA is an important negative regulator in controlling the erythroid differentiation of human myeloid leukemia cells. Cancer 2000;89:1004–11. © 2000 American Cancer Society.

Computer analysis of protein phosphorylation site sequences revealed that transcriptional factors and viral oncoproteins are prime targets for regulation of proline-directed protein phosphorylation, suggesting an association of the proline-directed protein kinase (PDPK) family with neoplastic transformation and tumorigenesis. In this report, an immunoprecipitate activity assay of proline-directed protein kinase F(A)/glycogen synthase kinase-3alpha (PDPK F(A)/GSK-3alpha) has been optimized to demonstrate significantly increased (p0.01) activity in poorly differentiated human prostate carcinoma PC-3 cells (55.5+/-3.8 units/mg) when compared to well-differentiated LNCaP cells (28.1+/-2.3 units/mg). Immunoblotting analysis revealed that increased activity of this PDPK in PC-3 cells is due not to overexpression of the protein, but to enhanced tyrosine phosphorylation of the kinase. When treated with genistein (a protein tyrosine kinase PTK inhibitor), the enhanced tyrosine phosphorylation/activation of the kinase in PC-3 cells can be blocked. Conversely, when treated with vanadate (a protein tyrosine phosphatase PTP inhibitor), the phosphotyrosine content of PDPK F(A)/GSK-3alpha in LNCaP cells can be promoted to the level of PC-3 cells. In sharp contrast, the PTK inhibitor has little effect on the tyrosine phosphorylation level of the kinase in LNCaP cells, whereas the PTP inhibitor has little effect on the tyrosine phosphorylation level of the kinase in PC-3 cells. Taken together, the results provide initial evidence that the tyrosine phosphorylation/activation levels of this oncogenic PDPK can be differentially regulated in well- and poorly differentiated prostate carcinoma cells.

Background In the process of epithelial mesenchymal transition EMT, the disassembly of junctional adhesion complexes such as E-cadherin is a remarkable sign during changes in cell morphology and polarity. However, E-cadherin expression is dynamic, and is regulated by the cellular endocytic system; it is also involved in cell signaling mechanisms. In this study, we investigated the role of E-cadherin in colorectal tumors and the relationship with recycling endosome protein Rab11 in colon cell transformation. Methods For tissue screening, the expressions of E-cadherin and Rab11 in colorectal tumors were identified by immunohistochemistry in 113 patients with colorectal carcinoma. For the in vitro cell experiment, GFP-tagged Rab11 plasmid was transfected into HT29 colon cells, E-cadherin expression and cell transformation were monitored by Western blot and confocal microscopy. Results In immunohistochemistry, the mean score of E-cadherin in tumor and normal tissues was 1.41 ± 0.06 and 1.08 ± 0.06 (p

Ellagic acid (EA) is able to inhibit the growth of several cancer cells; however, its effect on human ovarian carcinoma cells has not yet been investigated. Ovarian carcinoma ES-2 and PA-1 cells were treated with EA (10~100 μM) and assessed for viability, cell cycle, apoptosis, anoikis, autophagy, and chemosensitivity to doxorubicin and their molecular mechanisms. EA inhibited cell proliferation in a dose- and time-dependent manner by arresting both cell lines at the G1 phase of the cell cycle, which were from elevating p53 and Cip1/p21 and decreasing cyclin D1 and E levels. EA also induced caspase-3-mediated apoptosis by increasing the Bax : Bcl-2 ratio and restored anoikis in both cell lines. The enhancement of apoptosis and/or inhibition of autophagy in these cells by EA assisted the chemotherapy efficacy. The results indicated that EA is a potential novel chemoprevention and treatment assistant agent for human ovarian carcinoma.

Collective cell migration, whereby the cell-cell contacts such as E-cadherin are maintained during migration, has recently emerged, and the detailed mechanisms of this process are still unclear. The present study identified the role of Rab11 which functions in recycling endosome and the relation to E-cadherin in colorectal carcinoma and clarified the mechanism of Rab11 in the collective cell migration of cancer cells. The relationships between the overexpression of Rab11 and E-cadherin and survival were evaluated from colorectal carcinoma patients. A total of 107 patients with surgically resected colorectal carcinoma were enrolled in immunohistochemical study. The relationships between the overexpression of Rab11 and E-cadherin and survival were evaluated. GFP tagged Rab11 or Rab11 shRNA was introduced into HT-29 colon cancer cells for overexpression or knockdown. The interaction between E-cadherin and Rab11 was determined by immunoprecipitation. Rac1 and matrix metalloproteinase (MMP) activities were evaluated as functional effectors of collective cell migration. In the results, the expression of Rab11 and E-cadherin was not correlated with the stages of cancer or lymph node metastasis. However, the overall survival was poor in the group of 60 patients with duo-positive Rab11 and E-cadherin expression compared to the group (47 patients) without duo-positive expression (p = 0.038). In the cell biology assay, Rab11 was demonstrated through its physical interaction with E-cadherin, and overexpression of Rab11 was found to promote collective cell migration through the increased distribution of E-cadherin, which enhanced cell-cell connections. In addition, Rac1 activation and MMP2 expression were up-regulated upon Rab11 expression. This study demonstrated that Rab11and E-cadherin expression are poor indicators of survival time in colorectal carcinoma, but that Rab11 overexpression may contribute to increased collective cell invasion in colorectal carcinoma. Citation Format: Yuan-Chiang Chung, Wan-Chen Wei, Chia-Nung Hung, Chih-Ping Hsu, Hsiang-Ling Chiu, King-Jen Chang, Wei-Ting Chao. Overexpression of Rab11 and E-cadherin promotes collective cell migration and indicates a poor prognosis in colorectal carcinoma. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 1544.

The Litchi (Litchi chinensis) fruit products possess rich amounts of flavanoids and proanthocyanidins. Its pericarp has been shown to inhibit breast and liver cancer cell growth. However, the anticolorectal cancer effect of Litchi seed extract has not yet been reported. In this study, the effects of polyphenol-rich Litchi seed ethanol extract (LCSP) on the proliferation, cell cycle, and apoptosis of two colorectal cancer cell lines Colo320DM and SW480 were examined. The results demonstrated that LCSP significantly induced apoptotic cell death in a dose-dependent manner and arrested cell cycle in G2/M in colorectal carcinoma cells. LCSP also suppressed cyclins and elevated the Bax : Bcl-2 ratio and caspase 3 activity. This study providesin vitroevidence that LCSP serves as a potential chemopreventive agent for colorectal cancer.

BACKGROUND It has been shown previously that proline-directed protein kinase FA (PDPK FA) is overexpressed in various human malignancies compared with its expression in normal controls, and the suppression of overexpressed PDPK FA is capable of inhibiting the growth of various types of human carcinoma cells, suggesting a role for this PDPK in human malignancies. In this report, the authors combine immunohistologic, molecular, cellular, and clinicopathologic studies to demonstrate further an essential critical role for overexpressed PDPK FA in bladder carcinoma invasion, chemoresistance, and poor prognosis. METHODS The expression and localization of PDPK FA were analyzed by the immunohistochemical staining of specimens obtained from patients with primary transitional cell carcinoma (TCC) of the bladder. The stable antisense clones of human bladder carcinoma cells with specific suppression of overexpressed PDPK FA were established for invasion and chemosensitivity studies. RESULTS The immunohistochemical study revealed that PDPK FA was overexpressed preferentially in the invasive bladder carcinoma tissues. It was found that the stable antisense clones with specific suppression of overexpressed PDPK FA to ≈40% of the parental control level were capable of inhibiting the invasive activity and simultaneously enhancing the chemosensitivity of bladder carcinoma cells to various therapeutic drugs, such as vinblastine, vincristine, paclitaxel, and bleomycin. Clinicopathologic studies also revealed a correlation between overexpressed PDPK FA and disease recurrence/survival in patients with primary TCC (P < 0.05). CONCLUSIONS Taken together, the results demonstrate an essential critical role of overexpressed PDPK FA in invasion, chemoresistance, and poor prognosis. Suppression of overexpressed PDPK FA may provide a new potential target for therapeutic intervention aimed at preventing chemoresistance, disease progression, and recurrence in patients with bladder carcinoma. Cancer 2002;95:775–83. © 2002 American Cancer Society. DOI 10.1002/cncr.10731

In the process of epithelial mesenchymal transition EMT, the disassembly of junctional adhesion complexes such as E-cadherin is a remarkable sign during changes in cell morphology and polarity. However, E-cadherin expression is dynamic, and is regulated by the cellular endocytic system; it is also involved in cell signaling mechanisms. In this study, we investigated the role of E-cadherin in colorectal tumors and the relationship with recycling endosome protein Rab11 in colon cell transformation. For tissue screening, the expressions of E-cadherin and Rab11 in colorectal tumors were identified by immunohistochemistry in 113 patients with colorectal carcinoma. For the in vitro cell experiment, GFP-tagged Rab11 plasmid was transfected into HT29 colon cells, E-cadherin expression and cell transformation were monitored by Western blot and confocal microscopy. In immunohistochemistry, the mean score of E-cadherin in tumor and normal tissues was 1.41 ± 0.06 and 1.08 ± 0.06 (p < 0.05). The mean score of Rab11 in tumor and normal tissues was 0.51 ± 0.05 and 0.18 ± 0.02 (p < 0.05). Synchronous overexpression of E-cadherin and Rab11 was noted in 74 patients (66.5%) with colorectal carcinoma. When GFP-tagged Rab11 plasmid was overexpressed in cultured colon cell line HT-29, the E-cadherin expression was up-regulated, and a fibroblast-like cell polarity was induced, which resulted in cell transformation. This study demonstrated the importance of the overexpression of Rab11 and E-cadherin in colorectal cancer. The results indicated that Rab11 together with E-cadherin might be potential markers for colorectal cancer progression and treatment. Citation Format: Yuan-Chiang Chung, Wan-Chen Wei, Shin-Han Huang, Chi-Min Shih, Chih-Ping Hsu, King-Jen Chang, Wei-Ting Chao. Rab11 regulates E-cadherin expression and induces cell transformation in colorectal carcinoma. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 3166. doi:10.1158/1538-7445.AM2014-3166

Initial studies revealed that proline-directed protein kinase FA(PDPK FA) was overexpressed in various cancerous tissues relative to normal controls. However, the functional role of overexpressed PDPK FAin cancer remains to be established. In this report, we explore the potential role of PDPK FAin leukaemia cell growth by investigating the effects of partial inhibition of this kinase on the malignant phenotype of human chronic myeloid leukaemia cells (K562). Cloning of PDPK FAcDNA and its recombinant antisense expression vector and PDPK FA-specific antibody were successfully developed. Two stable antisense clones of K562 cells were subcloned which expressed 70% and 45% of PDPK FArespectively, compared with control-transfected clone in both immunoprecipitate activity assay and immunoblot analysis. In sharp contrast, these two antisense clones expressed no significant suppression of any other related PDPK family members, indicating the specificity of these two antisense clones. Moreover, these antisense clones proportionally and potentially exhibited cell growth retardation, poor clonogenic growth in soft agar and loss of serum independence. The results demonstrate that specific antisense suppression of PDPK FAis sufficient to interfere with the growth of K562 cells, indicating that PDPK FAis essential for human chronic myeloid leukaemia cell growth. © 2000 Cancer Research Campaign