Synemin is a large intermediate filament protein that has been identified in all types of muscle cells. It plays a role in human muscle diseases; however, the role of synemin in tumor cell transformation has rarely been investigated. Because hepatocellular carcinoma cells are morphologically different from normal human hepatocytes, we hypothesized that altered synemin expression and cytoskeletal disorganization might underlie this pleomorphic transformation. To test this hypothesis, we studied synemin expression in hepatocellular carcinoma and liver tissues by immunohistochemistry and immunoblotting. In addition, we analyzed the expression level and organization of all cytoskeletal elements after synemin knock-down in human Chang liver cells. Previously we found that plectin knock-down in human Chang liver cells causes a reduction in cytokeratin 18 expression with effects on intermediate filament disorganization and altered cellular morphology. In this study we also compared the effects of synemin knock-down and plectin knock-down on the cytoskeleton expression and organization. The results revealed that synemin expression was down-regulated in human hepatocellular carcinoma compared with normal liver, which is similar to the plectin expression. Surprisingly, the expression of cytoskeletal elements (cytokeratin 18, actin and tubulin) was not influenced by synemin knock-down in human Chang liver cells. The organization of cytoskeletal networks was also unaltered after synemin knock-down. In conclusion, both plectin and synemin are down-regulated in human hepatocellular carcinoma in vivo and transformed human liver cell in vitro. However, the mechanism of cell transformation caused by synemin knock-down is different from that of plectin knock-down. Plectin, but not synemin, knock-down provoked liver cell transformation via suppressing cytokeratin 18 expression and disrupting intermediate filament networks. Synemin knock-down did not influence the cytoskeleton expression and organization of human Chang liver cells.
Plectin is a cross-linking protein that organizes the cytoskeleton into a stable meshwork that helps maintain the uniform size and shape of cells. As cells of hepatocellular carcinoma are morphologically different from healthy human hepatocytes, we hypothesized that plectin deficiency and cytoskeletal disorganization underlies this pleomorphic transformation. To test this hypothesis we induced apoptosis as the most accessible pathway for creating plectin deficiency status in vivo. We analyzed expression levels and organization of plectin and other cytoskeletal elements, including intermediate filaments, microfilaments, and microtubules, after staurosporine-induced apoptosis in human Chang liver cells. The results revealed the expression of plectin and cytokeratin 18 were downregulated in hepatocellular carcinoma tissues in vivo. The expression of actin and tubulin, however, were not altered. In vitro analysis indicated that plectin and cytokeratin 18 were cleaved following staurosporine-treatment of human Chang liver cells. Time course experiments revealed that plectin was cleaved 2h earlier than cytokeratin 18. The organization of plectin and cytokeratin 18 networks collapsed after staurosporine-treatment. Conclusively, degradation of plectin induced by staurosporine-treatment in liver cells resulted in cytoskeleton disruption and induced morphological changes in these cells by affecting the expression and organization of cytokeratin 18.
Metastasis suppressors and associated other regulators of cell motility play a critical initial role in tumor invasion and metastases. Benzyl isothiocyanate (BITC) is a hydrolysis compound of glucotropaeolin in dietary cruciferous vegetables. BITC has been found to exhibit prevention of cancers in laboratory animals and might also be chemoprotective in humans. Here, the purpose of this study was to investigate the effects of BITC on cell proliferation, migration, invasion and mitogen-activated protein kinase (MAPK) pathways of AGS human gastric cancer cells. Wound healing and Boyden chamber (migration and invasion) assays demonstrated that BITC exhibited an inhibitory effect on the abilities of migration and invasion in AGS cancer cells. BITC suppressed cell migration and invasion of AGS cells in a dose-dependent manner. Results from Western blotting indicated that BITC exerted an inhibitory effect on the ERK1/2, Ras, GRB2, Rho A, iNOS, COX-2 for causing the inhibitions of MMP-2, -7 and -9 then followed by the inhibitions of invasion and migration of AGS cells in vitro. BITC also promoted MKK7, MEKK3, c-jun, JNK1/2, VEGF, Sos1, phosphoinositide 3-kinase (PI3K), PKC, nuclear factor-kappaB (NF-κB) p65 in AGS cells. Results from real-time polymerized chain reaction (PCR) showed that BITC inhibited the gene expressions of MMP-2,-7 -9, FAK, ROCK1 and RhoA after BITC treatment for 24 and 48 hours in AGS cells. Taken together, the finding may provide new mechanisms and functions of BITC, which inhibit migration and invasion of human gastric cancer AGS cells.
Plectin is a versatile cytoplasmic cross-linking protein that connects intermediate filaments to microfilaments, microtubules, and membrane adhesion sites. The cross-linking functions of plectin help organize the cytoskeleton into a stable meshwork important for maintaining uniformity in cell size and shape. As cells of hepatocellular carcinoma are morphologically different from normal human hepatocytes, we hypothesized that altered plectin expression and cytoskeletal organization underlies this pleomorphic transformation. To test this hypothesis, we analyzed expression levels and organization of all cytoskeletal elements, including intermediate filaments, microfilaments, and microtubules, after plectin knockdown in human Chang liver cells. We found that expression of cytokeratin 18, but not actin or tubulin, was downregulated by suppression of plectin protein. Furthermore, cytokeratin networks were partially collapsed and actin-rich stress fibers were increased. The organization of microtubule networks, by contrast, was unaltered. These findings support our hypothesis that, via effects on cytoskeletal organization, plectin deficiency might play an important role in the transformation of human liver cells.
Cancer metastasis involves multiple processes which may complicate clinical management and even lead to death. Matrix metalloproteinases (MMPs) play an important role in cancer cell invasion, metastasis and angiogenesis, depending on whether agents can inhibit MMPs which could lead to inhibition of the migration and invasion of cancer cells. Curcumin, the active constituent of the dietary spice turmeric, has potential for the prevention and therapy of cancer. However, there is no study to address the effects of curcumin on migration and invasion of mouse-rat hybrid retina ganglion cells (N18). This is the first study to explore the anti-migration and -invasion of curcumin in mouse-rat hybrid retina ganglion cells (N18) in vitro. Curcumin exerted a dose- and time-dependent inhibitory effect on the invasion and migration of N18 cells in vitro. Results from Western blotting showed that curcumin inhibited the protein levels of PKC, FAK, NF-kappaB p65 and Rho A leading to the inhibition of ERK1/2, MKK7, COX-2 and ROCK1, respectively, finally causing the inhibition of MMP-2 and -9 for the inhibition of migration and invasion of N18 cells. Moreover, this action was involved in the inhibition of gene expression of MMP-2 and -7, FAK, ROCK1 and Rho A. Overall, the above data show that the anticancer effect of curcumin also exists for the inhibition of migration and invasion in N18 cells, and that curcumin may be a powerful candidate for developing preventive agents for cancer metastasis.
Emodin was isolated from Rheum palmatum L. and exhibits an anticancer effect on human cancer cell lines, however, the molecular mechanisms of emodin-mediated apoptosis in human tongue cancer cells have not been fully investigated. In this study, treatment of human tongue cancer SCC-4 cells with various concentrations of emodin led to G2/M arrest through promoted p21 and Chk2 expression but inhibited cyclin B1 and cdc2; it also induced apoptosis through the pronounced release of cytochrome c from mitochondria and activations of caspase-9 and caspase-3. These events were accompanied by the generation of reactive oxygen species (ROS), disruption of mitochondrial membrane potential (delta psi(m)) and a decrease in the ratio of mitochondrial Bcl-2 and Bax content; emodin also promoted the levels of GADD153 and GRP78. The free radical scavenger N-acetylcysteine and caspase inhibitors markedly blocked emodin-induced apoptosis. Taken together, these findings suggest that emodin mediated oxidative injury (DNA damage) based on ROS production and ER stress based on the levels of GADD153 and GRP78 that acts as an early and upstream change in the cell death cascade to caspase- and mitochondria-dependent signaling pathways, triggers mitochondrial dysfunction from Bcl-2 and Bax modulation, mitochondrial cytochrome c release and caspase activation, consequently leading to apoptosis in SCC-4 cells.
Curcumin (diferuloylmethane), a phenolic compound from the plant Curcuma longa (Linn.) has been shown to exhibit antitumor activity and apoptosis in many human cancer cell lines including that of lung and liver cancer. In this study, curcumin was evaluated in BALB/c mice for its ability to inhibit pulmonary and liver adenoma formation and growth after they were orally treated with N-bis(2-hydroxypropyl)nitrosamine (DHPN). Animals were treated with DHPN in water for approximately 14 days before multiple doses of curcumin were given intraperitoneally. It was found that 200 microM curcumin reduced lung and liver tumor multiplicity by 37% (p<0.05) and 30% (p<0.05) respectively. The results indicated that curcumin significantly inhibited pulmonary and liver adenoma formation and growth in BALB/c mice. The precise mechanism by which curcumin inhibits lung and liver tumorigenesis remains to be elucidated. Thus, curcumin appears to be a promising new chemotherapeutic and preventive agent for lung and liver cancer induced by DHPN.
Gallic acid is a polyhydroxyphenolic compound which can be found in various natural products. It is recognized to be an excellent free radical scavenger and has been shown to induce apoptosis in lung cancer and leukemia cells. No report has addressed whether gallic acid affects mouse leukemia cells in vivo. In this study, we examined the in vivo effects of gallic acid on leukemia WEHI-3 cells and on macrophage phagocytosis. Gallic acid caused a significant decrease in the weights of the spleens and livers from BALB/c mice. One of the major characteristic of WEHI-3 leukemia is the enlarged spleen in mice after i.p. injection of WEHI-3 cells. Gallic acid did not affect the percentages of CD3, CD11 and CD19 markers but decreased the percentage of Mac-3 in a high-dose (80 mg/kg) treatment while promoting Mac-3 levels in a low-dose (40 mg/kg) treatment. Gallic acid promoted the activity, of macrophage phagocytosis in the white blood cells from peripheral blood mononuclear cells (PBMCs) at 40 and 80 mg/kg treatment doses, but decreased the macrophage phagocytosis in isolated peritoneal cells at the 80 mg/kg dose.
Aloe-emodin, one of the anthraquinones, has been shown to have anticancer activity in different kinds of human cancer cell lines. Therefore, the purpose of this study was to investigate the anti-cancer effect of aloe-emodin on human tongue squamous carcinoma SCC-4 cells. The results indicated that aloe-emodin induced cell death through S-phase arrest and apoptosis in a dose- and time-dependent manner. Treatment with 30 microM of aloe-emodin led to S-phase arrest through promoted p53, p21 and p27, but inhibited cyclin A, E, thymidylate synthase and Cdc25A levels. Aloe-emodin promoted the release of apoptosis-inducing factor (AIF), endonuclease G (Endo G), pro-caspase-9 and cytochrome c from the mitochondria via a loss of the mitochondrial membrane potential (DeltaPsi(m)) which was associated with a increase in the ratio of B-cell lymphoma 2-associated X protein (Bax)/B cell lymphoma/leukemia-2 (Bcl-2) and activation of caspase-9 and -3. The free radical scavenger N-acetylcysteine (NAC) and caspase inhibitors markedly blocked aloe-emodin-induced apoptosis. Aloe-emodin thus induced apoptosis in the SCC-4 cells through the Fas/death-receptor, mitochondria and caspase cascade. Aloe-emodin could be a novel chemotherapeutic drug candidate for the treatment of human tongue squamous cancer in the future.
In this study, we investigated the effects of DADS on human colon cancer cell line COLO 205 on cell cycle arrest and apoptosis in vitro. After 24 h treatment of COLO 205 cells with DADS, the dose- and time-dependent decreases of viable cells were observed and the IC50 was 22.47 μM. The decreased percentages of viable cells are associated with the production of ROS. Treatment of COLO 205 cells with DADS resulted in G2/M phase arrest and apoptosis occurrence through the mitochondrial-pathway (Bcl-2, Bcl-xL down-regulation and Bak, Bax up-regulation). DADS increased cyclin B, cdc25c-ser-216-9 and Wee1 but did not affect CDK1 protein and gene expression within 24 h of treatment. DADS-induced apoptosis was examined and confirmed by DAPI staining and DNA fragmentation assay. DADS promoted caspase-3, -8 and -9 activity and induced apoptosis were accompanied by increasing the levels of Fas, phospho-Ask1 and -JNK, p53 and decreasing the mitochondrial membrane potential which then led to release the cytochrome c, cleavage of pro-caspase-9 and -3. The COLO 205 cells were pre-treated with JNK inhibitor before leading to decrease the percentage of apoptosis which was induced by DADS. Inhibition of caspase-3 activation blocked DADS-induced apoptosis on COLO 205 cells.
BACKGROUNDPreviously we found some low molecular weight proteins identified as histone in hepatocelluar carcinoma. Our objective was to clarify whether the coimmunoprecipitation of histone and cytokeratin 18 was an artifact or not.MATERIALS AND METHODSHistone 3 and cytokeratin 18 were investigated in three cases of human hepatocellular carcinoma and one case of normal liver tissue. Nuclei of the tissues were isolated; the proteins inside the nuclei were analyzed by Western blot.RESULTSThe results revealed histone was co-immunoprecipitated with cytokeratin 18 in hepatocellular carcinoma. It was speculated that modulation of the cytoskeleton in human hepatocellular carcinoma might disturb the organization of the nucleoskeleton. The unstable nucleoskeleton might further cause instability and fragility of nuclei, thus possibly exposing the histone and co-immunoprecipitating it with cytokeratin 18.CONCLUSIONThe evidence might indicate that expression of histone 3 was highly related to modulation of cytokeratin 18 and might play an important role in tumorigenesis of hepatocellular carcinoma.
The mechanisms of apoptosis induced by diallyl disulfide (DADS) were explored in human cervical cancer Ca Ski cells. Flow cytometric analysis, DNA gel electrophoresis and DAPI staining demonstrated that DADS induced apoptosis in Ca Ski cells. DADS induced apoptosis through the production of reactive oxygen species and Ca2+, and induced abrogation of mitochondrial membrane potential (Deltapsim) and cleavage of Bid protein (t-Bid). DADS increased the levels of p53, p21 and Bax, but caused a decrease in the level of Bcl-2. DADS also promoted the activities of caspase-3 leading to DNA fragmentation, thus indicating that DADS-induced apoptosis is caspase-3 dependent. In addition, DADS induced an increase in the level of cytochrome c in the cytoplasm, which was released from mitochondria. BAPTA attenuated the Deltapsim abrogation and significantly diminished the occurrence of DADS-induced apoptosis in Ca Ski cells. In conclusion, DADS-induced apoptosis occurs via production of ROS and caspase-3 and a mitochondria-dependent pathway in Ca Ski cells.
Background: Hepatoma cells are morphologically different from those of the normal liver. Intermediate filaments (IFs) are important in building the cellular architecture and maintaining the outline of cells. Plectin is a cross-linking protein that organizes the cytoskeleton into a stable meshwork, which can maintain the uniform size and shape of hepatocytes. Apoptosis might be the most possible pathway for creating plectin deficiency in the in vivo state. Materials and Methods: Apoptosis was induced by staurosporine (STS) treatment in liver cells. The protein expression of cytokeratin 18 (CK18) and plectin as well as the morphology of the liver cells and the distribution of CK18 and plectin in the cells was studied after STS treatment. Results: Plectin was cleaved in the liver cells during apoptosis and CK18 was modulated. Morphological changes were observed in the liver cells. Conclusion: By affecting the organization of IFs, plectin might play an important role in the pleomorphism of hepatoma cells and even the tumorigenesis of hepatoma.
Intermediate filaments are important in building the cellular architecture. Previously we found cytokeratin18 was modulated in human hepatocellular carcinoma. Plectin is a cross-linking protein that organizes the cytoskeleton into a stable meshwork, which can maintain the uniform size and shape of hepatocytes. Because the cells of hepatocellular carcinoma were morphologically different from the hepatocytes, we speculated that expression of plectin and organization of intermediate filament might play roles in the pleomorphism of hepatocellular carcinoma cells. In this paper, we studied the plectin expression of hepatocellular carcinoma and liver tissues by immunohistochemistry and immunoblot. The results revealed that plectin was deficient and cytokeratin18 was modulated in hepatocellular carcinoma. Furthermore, we knockdown the plectin mRNA in Chang cells, the result revealed the plectin was deficient and the organization of cytokeratin18 was altered. Conclusively, this study offers a hypothesis that plectin deficient might play an important role in the tumorigenesis of hepatocellular carcinoma.
The effects of berberine on the in vivo N-acetylation and metabolism of 2-aminofluorene (2-AF) in bladder, blood, colon, kidney, liver, feces and urine samples and brain tissues (cerebrum, cerebellum and pineal gland) of male Sprague-Dawley rats were investigated. Major metabolites, such as 1-OH-2-AAF, 3-OH-2-AAF, 8-OH-2-AAF and 9-OH-2-AAF were found in bladder tissues, 1-OH-2-AAF, 5-OH-2-AAF and 8-OH-2-AAF were found in blood samples, 1-OH-2-AAF, 3-OH-2-AAF, 5-OH-2-AAF, 8-OH-2-AAF and 9-OH-2-AAF were found in colon tissues, 1-OH-2-AAF, 3-OH-2-AAF and 9-OH-2-AAF were found in kidney tissues, 1-OH-2-AAF, 3-OH-2-AAF and 8-OH-2-AAF were found in liver tissues, 1-OH-2-AAF, 3-OH-2-AAF, 5-OH-2-AAF, 7-OH-2-AAF, 8-OH-2-AA and 9-OH-2-AAF were found in feces samples and 1-OH-2-AAF, 3-OH-2-AAF, 5-OH-2-AAF, 7-OH-2-AAF, 8-OH-2-AA and 9-OH-2-AAF were also found in urine samples, 1-OH-2-AAF, 3-OH-2-AAF and 8-OH-2-AAF were found in cerebrum tissues, 1-OH-2-AAF, 3-OH-2-AAF and 7-OH-2-AAF were found in cerebellum tissues. In the control group, however, only 2-AF and 2-AAF were found in pineal gland after rats had been orally treated with 2-AF (50 mg/kg) for 24 h. Pre-treatment of male rats with berberine (40 mg/kg) 24 h prior to the administration of 2-AF (50 mg/kg), as well as the co-administration of berberine and 2-AF led to a decrease in the amounts of 3-OH-2-AAF and an increase in the amounts of 8-OH-2-AAF in bladder tissues. In blood samples, there were significant decreases of 2-AF, 2-AAF, 1-OH-2-AAF and 8-OH-2-AAF, after rats were pre-treated with berberine for 24 h before the addition of 2-AF. However, co-administration of berberine and 2-AF led to an increase in the amounts of 5-OH-2-AAF. In colon tissues, there were significant decreases of 2-AF, 2-AAF, 1-OH-2-AAF and 8-OH-2-AAF in colon samples after rats were treated with berberine for 24 h before the addition of 2-AF. 2-AF, 1-OH-2-AAF, 3-OH-2-AAF and 9-OH-2-AAF levels were significantly different between control and the group treated with berberine and 2-AF at the same time. In kidney tissues, significant decreases of 2-AF and 2-AAF and of 3-OH-2-AAF were observed after rats were treated with both compounds separately and simultaneously. However, 24 h berberine pre-treatment followed by addition of 2-AF led to significant increase of 9-IH-2-AAF. In liver tissues, there were significant decreases of 2-AAF and 1-OH-2-AAF, after co-administration of berberine and 2-AF. The amounts of 2-AAF, 1-OH-2-AAF and 3-OH-2-AAF were significantly different between the control and the group pretreated with berberine 24 h before the addition of 2-AF. In the feces samples, there were significant decreases of 2-AAF, 3-OH-2-AAF, 7-OH-2-AAF, 8-OH-2-AAF and 9-OH-2-AAF after co-administration of berberine and 2-AF. However, the berberine pre-treatment followed by addition of 2-AF led to a significant increase of 2-AF, 2-AAF and 1-OH-2-AAF levels. In urine samples, there were significant differences of 2-AF, 2-AAF, 1-OH-2-AAF, 3-OH-2-AAF, 5-OH-2-AAF, 8-OH-2-AAF and 9-OH-2-AAF after the co-treatment. However, berberine treatment followed by 2-AF led to significant differences in 1-OH-2-AAF and 5-OH-2-AAF levels. In the cerebrum samples, there were significant differences in 1-OH-2-AAF and 8-OH-2-AAF after both berberine co-treatment and pre-treatment. In cerebellum samples, there were also significant differences in the 1-OH-2-AAF and 3-OH-2-AAF levels after both co- and pretreatment. In pineal gland samples, there were significant differences in 2-AAF levels after co-treatment with berberine and 2-AF and 1-OH-2-AAF was also found in both groups. However, berberine pre-treatment followed by 2-AF led to different levels of 2-AF and 2-AAF, but not of 3-OH-2-AAF.
Intermediate filaments are important in building the architecture of liver cells and are proposed to interact with other cellular components. Among intermediate filament associated proteins, plectin is a versatile cytoskeletal linkage protein which has been shown to interact with a variety of cytoskeletal structures. Intermediate filament and plectin might play some roles in tumorigenesis of human hepatocellular carcinoma since cells of hepatocellular carcinoma were morphologically different from normal liver. Plectin exhibited wide distribution spectrum among various tissues, however, it was poorly investigated in human liver and hepatoma tissues. In this paper, we studied the plectin expression in 18 cases of human hepatocellular carcinoma and normal hepatocytes by immunohistochemistry. The results revealed that plectin expression was deficient in human hepatocellular carcinoma and was probably through post-translational modification. Many 0.4 to 0.8 microm-thick keratin bundles were found in intermediate filament extracts of liver and hepatoma tissues. These bundles were greater in diameter about 40 to 80 times of single intermediate filament. We speculated that intermediate filament organized into "filament bundles" to maintain the shape of normal cells. In cancer cells, plectin was deficient and the irregularly loosened filament bundles could cause pleomorphism of cancer cells.
Low-power laser therapy has become popular in clinical applications including promoting wound healing and pain relief. However, effects of this photoradiation on human hepatoma cells are rarely studied. Previously, we found 808 nm gallium aluminum arsenide (GaAlAs) continuous wave laser had an inhibitory effect on the proliferation of human hepatoma cell lines HepG2 and J-5 at the energy density of 5.85 and 11.7 J/cm(2), respectively. The aim of the present study was to evaluate the possible mechanism of action of this photoradiation on HepG2 and J-5 cells. HepG2 and J-5 cells were cultured in 24-well plates for 24 h. After photoradiation by 130 mW 808 nm GaAlAs continuous wave laser for different time intervals (0, 30, 60, 90, 120, 150, and 180 s), Western blot and immunofluorescent staining were used to examine the expression and distribution of histone and cytoskeletal proteins. The cell counts as well as histone and synemin expression of HepG2 and J-5 cells were reduced by photoradiation at the energy density of 5.85 and 11.7 J/cm(2), respectively. Furthermore, the architecture of cytoskeletons and the distribution of intermediate filament-associated proteins (plectin and synemin) were disorganized by photoradiation. Photoradiation by 808 nm GaAlAs continuous wave laser at the energy density of 5.85 and 7.8 J/cm(2) inhibited the survival of human hepatoma cell lines. The mechanism might reduce synthesis of histone and synemin. Reduced histone synthesis might further reduce the proliferation rate of these cells. Reduced synemin synthesis might result in the destruction of the cytoskeleton. Therefore, the net effects by this photoradiation were reduced cell survival.
The effects of berberine on growth, arylamine N -acetyltransferase (NAT) activity, and gene expression in Salmonella Typhi (Typhi) were described. The growth inhibition of Typhi was determined by measuring absorbance by optical density (OD at 650 nm). The NAT activity was determined by measuring the levels of 2-aminofluorene (AF) and N -acetyl-2-aminofluorene (AAF) by high-performance liquid chromatography. The results demonstrated that 24-h berberine treatment decreased bacteria growth and amounts of AAF in Typhi. Western blotting and flow cytometry were used for examining the levels of NAT after bacteria were cotreated with or without various concentrations of berberine, and results indicated that berberine decreased the levels of NAT in Typhi . Polymerase chain reaction was used for examining the gene expression of NAT (mRNA NAT), and results indicated that berberine affects mRNA NAT1 expression in Typhi .
Cells of human hepatocellular carcinoma (HCC) were morphologically different from those of normal liver. Intermediate filaments are important in building the architecture of liver cells and are proposed to interact with other cellular components. Synemin is one of intermediate filament associated proteins which can link between intermediate filament and other cytoskeletal structures. It was suggested that synemin might play some roles in tumorigenesis of hepatocellular cancinoma. In this study, we searched the synemin expression in 18 human HCCs by immunohistochemistry. The results revealed that synemin was modulated nearly in all human HCC cases. Many 0.4-0.8 microm-thick bundles were found in the IF extracts of liver and HCCs. These bundles were greater in diameter about 40 to 80 times of single IF. We speculated that the IFs were organized into the "filament bundles" to support the normal shape of the cells. That was, normal cell needed numerous synemin to lock the individual IF into stable "filament bundles". In cancer cells, the synemin was altered and this might lead to a loosened change of filament bundles, and the cancer cells would become pleomorphic.