Preclinical Efficacy of V⁴Q⁵dDAVP, a Second Generation Vasopressin Analog, on Metastatic Spread and Tumor-Associated Angiogenesis in Colorectal Cancer / Journal of the Korean Cancer Association, 대한암학회지

PURPOSE: Control of metastatic spread of colorectal cancer (CRC) remains as a major therapeutic challenge. [V4 Q5 ]dDAVP is a vasopressin peptide analog with previously reported anticancer activity against carcinoma tumors. By acting as a selective agonist of arginine vasopressin type 2 membrane receptor (AVPR2) present in endothelial and tumor cells, [V⁴Q⁵]dDAVP is able to impair tumor aggressiveness and distant spread. Our aim was to evaluate the potential therapeutic benefits of [V⁴Q⁵]dDAVP on highly aggressive CRC disease using experimental models with translational relevance. MATERIALS AND METHODS: Murine CT-26 and human Colo-205 AVPR2-expressing CRC cell lines were used to test the preclinical efficacy of [V⁴Q⁵]dDAVP, both in vitro and in vivo. RESULTS: In syngeneic mice surgically implanted with CT-26 cells in the spleen, sustained intravenous treatment with [V⁴Q⁵]dDAVP (0.3 µg/kg) dramatically impaired metastatic progression to liver without overt signs of toxicity, and also reduced experimental lung colonization. The compound inhibited in vivo angiogenesis driven by Colo-205 cells in athymic mice, as well as in vitro endothelial cell migration and capillary tube formation. [V⁴Q⁵]dDAVP exerted AVPR2-dependent cytostatic activity in vitro (IC₅₀ 1.08 µM) and addition to 5-fluorouracil resulted in synergistic antiproliferative effects both in CT-26 and Colo-205 cells. CONCLUSION: The present preclinical study establishes for the first time the efficacy of [V⁴Q⁵]dDAVP on CRC. These encouraging results suggest that the novel second generation vasopressin analog could be used for the management of aggressive CRC as an adjuvant agent during surgery or to complement standard chemotherapy, limiting tumor angiogenesis and metastasis and thus protecting the patient from CRC recurrence.

Chemical genomics reveals inhibition of breast cancer lung metastasis by Ponatinib via c-Jun

Metastasis is the leading cause of human cancer deaths. Unfortunately, no approved drugs are available for anti-metastatic treatment. In our study, high-throughput sequencing-based high-throughput screening (HTS) and a breast cancer lung metastasis (BCLM)-associated gene signature were combined to discover anti-metastatic drugs. After screening of thousands of compounds, we identified Ponatinib as a BCLM inhibitor. Ponatinib significantly inhibited the migration and mammosphere formation of breast cancer cells in vitro and blocked BCLM in multiple mouse models. Mechanistically, Ponatinib represses the expression of BCLM-associated genes mainly through the ERK/c-Jun signaling pathway by inhibiting the transcription of JUN and accelerating the degradation of c-Jun protein. Notably, JUN expression levels were positively correlated with BCLM-associated gene expression and lung metastases in breast cancer patients. Collectively, we established a novel approach for the discovery of anti-metastatic drugs, identified Ponatinib as a new drug to inhibit BCLM and revealed c-Jun as a crucial factor and potential drug target for BCLM. Our study may facilitate the therapeutic treatment of BCLM as well as other metastases.

Mesua ferrea stem bark extract induces apoptosis and inhibits metastasis in human colorectal carcinoma HCT 116 cells, through modulation of multiple cell signalling pathways / 中国天然药物

Considering the great potential of natural products as anticancer agents, the present study was designed to explore the molecular mechanisms responsible for anticancer activities of Mesua ferrea stem bark extract against human colorectal carcinoma. Based on MTT assay results, bioactive sub-fraction (SF-3) was selected for further studies using HCT 116 cells. Repeated column chromatography resulted in isolation of less active α-amyrin from SF-3, which was identified and characterized by GC-MS and HPLC methods. α-amyrin and betulinic acid contents of SF-3 were measured by HPLC methods. Fluorescent assays revealed characteristic apoptotic features, including cell shrinkage, nuclear condensation, and marked decrease in mitochondrial membrane potential in SF-3 treated cells. In addition, increased levels of caspases-9 and -3/7 levels were also observed in SF-3 treated cells. SF-3 showed promising antimetastatic properties in multiple in vitro assays. Multi-pathway analysis revealed significant down-regulation of WNT, HIF-1α, and EGFR with simultaneous up-regulation of p53, Myc/Max, and TGF-β signalling pathways in SF-3 treated cells. In addition, promising growth inhibitory effects were observed in SF-3 treated HCT 116 tumour spheroids, which give a hint about in vivo antitumor efficacy of SF-3 phytoconstituents. In conclusion, these results demonstrated that anticancer effects of SF-3 towards colon cancer are through modulation of multiple molecular pathways.

Meta-tyrosine: A powerful anti-metastatic factor with undetectable toxic-side effects

Concomitant tumor resistance (CR) is a phenomenon in which a tumor-bearing host is resistant to the growth of secondary tumor implants and metastasis. While former studies have indicated that T-cell dependent processes mediate CR in hosts bearing immunogenic small tumors, the most universal manifestation of CR induced by immunogenic and non-immunogenic large tumors had been associated with an antitumor serum factor that remained an enigma for many years. In a recent paper, we identified that elusive factor(s) as an equi-molar mixture of meta-tyrosine and ortho-tyrosine, two isomers of tyrosine that are not present in normal proteins and that proved to be responsible for 90% and 10%, respectively, of the total serum anti-tumor activity. In this work, we have extended our previous findings demonstrating that a periodic intravenous administration of meta-tyrosine induced a dramatic reduction of lung and hepatic metastases generated in mice bearing two different metastatic murine tumors and decreased the rate of death from 100% up to 25% in tumor-excised mice that already exhibited established metastases at the time of surgery. These anti-metastatic effects were achieved even at very low concentrations and without displaying any detectable toxic-side effects, suggesting that the use of meta-tyrosine may help to develop new and less harmful means of managing malignant diseases, especially those aimed to control the growth of metastases that is the most serious problem in cancer pathology.

La resistencia concomitante antitumoral (RC) es el fenómeno según el cual un individuo portador de tumor inhibe el crecimiento de implantes tumorales secundarios y metástasis. Si bien desde hace tiempo se sabe que la RC inducida por tumores inmunogénicos de pequeño tamaño es generada por mecanismos inmunológicos dependientes de células T, por otro lado, la manifestación más universal de la RC, generada tanto por tumores inmunogénicos como no-inmunogénicos de gran tamaño, había sido asociada con un (unos) factor sérico antitumoral cuya naturaleza permaneció elusiva por años. En un trabajo reciente, nuestro grupo de trabajo identificó este factor como la mezcla equi-molar de meta-tirosina y orto-tirosina, dos isómeros de tirosina que no están presentes en proteínas normales y que demostraron ser responsables del 90% y 10%, respectivamente, de la actividad antitumoral total del suero. En este trabajo, continuamos nuestras investigaciones demostrando que la administración periódica de meta-tirosina reducía drásticamente el número de metástasis pulmonares y hepáticas en ratones portadores de dos tumores murinos altamente metastásicos y disminuía dramáticamente la mortandad (de 100% a 25%) de ratones con metástasis ya establecidas al momento de la extirpación quirúrgica del tumor. Estos efectos anti-metastásicos se lograron aun con muy bajas concentraciones de meta-tirosina y sin efectos tóxicos perceptibles, lo que sugiere que su uso puede ayudar a diseñar nuevas y menos nocivas estrategias para el tratamiento del cáncer, especialmente aquellas destinadas a controlar el crecimiento metastásico, que es el problema más grave en la enfermedad oncológica.

Metastatic cancer stem cells and anti-metastasis strategies / 中国肿瘤生物治疗杂志

Cancer stem cells (CSC) are capable of self-renewal and can proliferate into a heterogeneous bulk with cancer progeny population, which is the main reason for recurrence and metastasis of cancer. Metastatic cancer stem cells (MCSC) have the properties of CSC and the ability of metastasis. Metastasis happens at both the late and early stages of tumorigenesis. MCSC are different from CSC in origin, epithelial-mesenehyrnal transition (EMT), mesenehymal-epithelial transition (MET), and microenvironment of target organs (niche), etc. Therefore, MCSC is the foundation of cancer metastasis. Anti-metastasis strategies include killing CSC, blocking EMT and MET of CSC, inhibiting MCSC adhesion to microvessels, and destroying MCSC dependent-niche. This review introduces the possible sources, biological features of MCSC, the possible breakthrough in MCSC research, and MCSC-targeted anti-metastasis strategy, hoping to provide reference for researches about tumor metastasis mechanisms and anti-metastasis strategies.

Effects of Nocodazole on Protein Synthesis Appratus of Tumor Cells / 대한해부학회지

Nocodazole is an anticancer agent that acts on microtubules or filaments. HeLa, Hep G2, A549, L929 and NIH/3T3 cell lines were cultivated in alpha-MEM with 3micrometer or 30micrometer nocodazole. To elucidate the associations between nocodazole`s antitumor actions and these effects, the influences of nocodazole on the cellular morphology and the organelles involving synthesis, secretion and destruction of proteins were investigated under light and electron microscopes. The changes of intermediate filaments such as pancytokeratins and vimentins that maybe suggest antimetastatic action of nocodazole were observed using immunocytochemical technique, PAP at light microscopic level. Rounded or micronucleate cells were induced by treatment with 3micrometer and 30micrometer nocodazole for 2 hours to 4 days. Multimicronucleate cells appeared in experimental groups of all cell lines. Nuclear foldings occurred in cells of experimental groups treated with nocodazole for 2-3 days. The numerical increases of rough endoplasmic reticulum were observed in HeLa cells treated with nocodazole for 3 days and the dilatation or numerical increases in L929 cells treated with nofodazole for 1-3 days. The fragmentations or dispersion of Golgi complex were observed in cells treated with nocodazole for 1-3 days. The amount of filaments increased in cells treated with nocodazole for 1-3 days. The number of lysosomes increased in cells treated with nocodazole for 1-3 days. The number of liposomes also increased in Hep G2 cells treated with 30micrometer nocodazole for 3 days and in 3micrometer & 30micrometer, 3 days group of 3T3 cells. The amount of pancytokeratins and vimentins increased in cells treated with nocodazole for 1-3 days. Taken together, depolymerization of microlubules was induced by nocodazole, and then the organization of cells was disintegrated. As a result, the rounded cells, the cells having multimicronuclei, and the changes of golgi complexes occurred. But there were relatively no great changes of rough endoplasmic reticulum. The amount of intermediate filaments that maintain the differentiated states of cells increased by nocodazole treatment. It was suggested that morphological changes of cells could be used in evaluation of actions of nocodazole. Especially, the increase of amount of intermediate filaments by nocodazole changed cells of each cell line from undifferentiated state to differentiated, and therefore the author hope that the changes in amount of intermediate filaments provide an important clue in anticancer and antimetastatic actions of nocodazole.

Effects of Nocodazole on Extracellular Matrix Proteins of Cancer Cell Lines / 대한해부학회지

Nocodazole is an anticancer agent, well-known for its antimetastatic activity that acts on microtubules, microfilaments and extracellular matrix proteins. Hela, Hep G2, A549, L929, and NIH/3T3 cell lines were cultivated in alpha-MEM with 3microM or 30microM nocodazole. To investigate the mechanism of nocodazole preventing tumor cell metastasis, the influences of nocodazole on the amounts of glycoprotein, fibronectin, laminin and actin were investigated using PAS staining and PAP technique at light microscopic level. Two designed models ; coverglass and 3-day-old rat heart fragments models, were used in observing the invasiveness of cancer cells. Partitularly the three-dimensional model coculturing cell lines and heart fragment was used in evaluating the migration and/or proliferation or the invasiveness of cell around the fragment, and observed under inverted or bright field light microscope. The amount of glycoprotein of all cell-lines increased in cells of groups treated with nocedazole for 1, 2 and 3 day. The amounts of fibronectin usually increased in cells of groups treated with nocodazole for 1, 2 and 3 day. The amounts of laminin increased in cells of groups treated with nocodazole. The amounts of actin usually increased in cells of groups treated with nocodazole for 1, 2 and 3 days. With the prolonging of nocodazole-treatment time in two dimensional model using coverglass, the cells of control group except Hep G2 cells formed monolayer in cell-free zone according to migration or proliferation of many cells. But only a few cells of experimental groups migrated or proliferated into cell-free zone. In rat heart fragment model the cells of control group showed the invasiveness into the fragment but few or none of the cells from experimental groups attached around the fragment. Taken together, nocodazole increased the synthesis of fibronectin and laminin in cells in place of depolymerizing microtubules. Therefore, the amounts of extracellular matrix proteins in the extracellular space increased. And the increase amounts of actin connected to the extracellular matrix proteins through the integrin of plasma membrane seemed to strengthen cell attachment because of accordance between the orientation of actin and extracellular matrix proteins. Since it is important for cancer cells` metastasis to secrete various enzymes to pass through extracellular matrix proteins, it is expected more difficult for the cells to metastasize into other regions due to the increase of extracellular matrix proteins. As a result of confirmation of antiinvasive actions using two kinds of model, nocodazole seems to be a valuable anti-metastatic agent by supressing the cell motility and consequently, the invasiveness into the fragment. Nocodazole at concentration of 3microM will be probably anticipated antimetastatic activity reflecting that the effects of nocodazole between 3microM and 30microM groups had no differences.