• Asian Pacific Journal of Cancer Prevention
• /
• 제13권8호
• /
• pp.4001-4005
• /
• 2012

Backgrouds: The hedgehog (Hh) signaling pathway is composed of patched (PTCH) and smoothened (SMO), two transmembrane proteins, and downstream glioma-associated oncogene homolog (Gli) transcription factors. Hh signaling plays a pathological role in the occurrence and development of various cancers. Methods: To investigate the expression of SMO protein in colon cancer and its association with clinicopathological parameters and postoperative liver metastasis, immunohistochemistry was performed with paraffin-embedded specimens of 96 cases. Relationships between SMO protein expression and clinicopathological parameters, postoperative liver metastasis were analyzed. Results: IHC examination showed that SMO protein expression was significantly increased in colon cancer tissues compared to normal colon tissues (P = 0.042), positively related to lymph node metastases (P = 0.018) and higher T stages (P = 0.026). Postoperative live metastasis-free survival was significantly longer in the low SMO expression group than in those with high SMO expression ($48.7{\pm}8.02$ months vs $28.0{\pm}6.86$ months, P=0.036). Multivariate analysis showed SMO expression level to be an independent prognostic factor for postoperative live metastasis-free survival (95% confidence interval [CI] =1.46-2.82, P = 0.008). Conclusions: Our results suggest that in patients with colon cancer, the SMO expression level is an independent biomarker for postoperative liver metastasis, and SMO might play an important role in colon cancer progression.

• Toxicological Research
• /
• 제14권4호
• /
• pp.569-575
• /
• 1998

One of the most frequent dejects in human cancer is the uncontrolled activation of the ms-signaling pathways. Significant evidence has accumulated to directly implicate members of the matrix metalloproteinases (MMPs) in tumor invasion and metastasis formation. We have previously shown that MMP-9 expression was significantly enhanced in the ras-tranfected HT1080 human fibrosarcoma cells at the mRNA level. In the present study, we investigated the roles of MMP-2 and -9 on the H-ras-induced invasive phenotypes of MCF 10A human breast epithelial cells and HT 1080 human fibrosarcoma cells. We show that H-ras is able to induce or enhance a signaling pathway leading to the enhancement of an invasive phenotype in both MCF10A and HT1080 cells as determined by matrigel invasion assay. We then examined the effect of H-ras activation on the expression of MMP-2 and -9 by measuring enzymatic activities and mRNA levels. Our data clearly demonstrated that H-ras prominently induces expression of MMP-2 in MCF10A cells, while it efficiently up regulates MMP-9 in HT1080 cells. Taken together, these findings suggest that the correlation between ras-mediated invasiveness and enhanced expression of MMPs may be cell type-specific: MMP-9 is closely associated with the invasive phenotype induced by ras activation in fibrosarcoma cells, whereas MMP-2 is more likely associated with it in epithelial cells.

• Molecules and Cells
• /
• 제25권1호
• /
• pp.131-137
• /
• 2008

Crk-associated substrate (CAS) is a focal adhesion protein that is involved in integrin signaling and cell migration. CAS deficiency reduces the migration and spreading of cells, both of which are processes mediated by Rac activation. We examined the functions of v-Crk, the oncogene product of the CT10 virus p47gag-crk, which affects cell migration and spreading, membrane ruffling, and Rac activation in CAS-deficient mouse embryonic fibroblasts (CAS-/- MEFs). CAS-/- MEFs showed less spreading than did CAS+/+ MEFs, but spreading was recovered in mutant cells that expressed v-Crk (CAS-/-v-Crk MEF). We observed that the reduction in spreading was linked to the formation of membrane ruffles, which were accompanied by Rac activation. In CAS-/- MEFs, Rac activity was significantly reduced, and Rac was not localized to the membrane. In contrast, Rac was active and localized to the membrane in CAS-/-v-Crk MEFs. Lamellipodia protrusion and ruffle retraction velocities were both reduced in CAS-/- MEFs, but not in CAS-/-v-Crk MEFs. We also found that microinjection of anti-gag antibodies inhibited the migration of CAS-/-v-Crk MEFs. These findings indicate that v-Crk controls cell migration and membrane dynamics by activating Rac in CAS-deficient MEFs.

• Asian Pacific Journal of Cancer Prevention
• /
• 제14권8호
• /
• pp.4501-4507
• /
• 2013

Caveolin-1 is a scaffold protein on the cell membrane. As the main component of caveolae, caveolin-1 is involved in many biological processes that include substance uptake and transmembrane signaling. Many of these processes and thus caveolin-1 contribute to cell transformation, tumorigenesis, and metastasis. Of particular interest are the dual rolesof tumor suppressor and oncogene that caveolin-1 appear to play in different malignancies, including pancreatic cancer. Therefore, analyzing caveolin-1 regulators and understanding their mechanisms of actionis key to identifying novel diagnostic and therapeutic tools for pancreatic cancer. This review details the mechanisms of action of caveolin-1 regulators and the potential significance for pancreatic cancer treatment.

• Asian Pacific Journal of Cancer Prevention
• /
• 제16권8호
• /
• pp.3505-3508
• /
• 2015

Background: Ras genes are thought to play an important role in human cancer since they have been found to be activated frequently in several types of tumors including breast cancer, where the overall incidence of K-RAS oncogene activation is 0-10%. Evaluation of K-RAS gene not only for mutational frequency but also for mutation types in this downstream signaling gene pathway is necessary to determine the mechanisms of action. The present study was conducted to test the hypothesis that K-RAS activation is involved in breast cancer risk of south Indian population. Materials and Methods: A total of 70 paired pathologically confirmed tumor and non-tumor tissues from the same breast cancer patients were analysed for most common K-RAS mutations of codon 12,13 and 61 by polymerase chain reaction followed by restriction digestion and direct nucleotide sequencing method. Results: We found that a high rate of homozygous and heterozygous mutations of codon 12, but not codon 13 and 61, may influence the invasive ductal carcinoma of breast risk in this study. Conclusions: Our study indicated that only codon 12 may be involved in initiating breast carcinogenesis in India.

• 한국응용과학기술학회지
• /
• 제25권3호
• /
• pp.370-379
• /
• 2008

Akt, a serine/threonine protein kinase as a viral oncogene, is a critical regulator of PI3K-mediated cell proliferation and survival. On translocation, Akt is phosphorylated and activated, ultimately resulting in stimulation of cell growth and survival. As a part of our program toward the novel Akt1 inhibitors with potent activity over PI3K signaling pathway, we found primary hit compound 2 with an $IC_{50}$ value of $620\mu}M$ from protein kinase focused library. Based on the structural features of 2, new 1,3,4-thiadiazole derivatives were designed by the introduction of aromatic and heteroaromatic moieties onto thiadiazole nucleus. In this work, a series of 1,3,4-thiadiazole derivatives 1a-1 were synthesized and evaluated for Akt1 inhibitory activity.

• Animal cells and systems
• /
• 제1권4호
• /
• pp.637-640
• /
• 1997

Raf-1, a cytoplasmic serine/threonine protein kinase, serves as a central intermediate in many signaling pathways in cell proliferation, differentiation, and development. In this study, we investigated that B-raf, Drosophila homolog of the human c-raf-1, is involved in ultraviolet (UV) responsive events by using hypomorphic mutant $D-raf^{c110}$ and Draf-lacZ transgenic fly. At first, effect of UV damage on the survival of wild-type and $D-raf^{C110}$ strains was examined. In terms of $1/LD_{50}$ value, the relative ratio of UV sensitivities of wild-type versus $D-raf^{C110}$ strain was 1 : 2.2. By using quantitative $\beta$-galactosidase activity analysis, transcriptional activity of the D-raf gene promoter was also examined in UV-irradiated Draf-lacZ transgenic larvae. UV irradiation increased the expression of lacZ reporter gene in Draf-lacZ transgenic fly. However, in $D-raf^{C110}$ strain the transcriptional activity of D-raf gene promoter by UV irradiation was extensively reduced. Results obtained in this study suggest that D-raf plays a role in UV response, leading to better survival of Drosophila to UV damage.

• 생명과학회지
• /
• 제30권11호
• /
• pp.973-982
• /
• 2020

본 연구는 지방구세포 감소를 위한 소재개발로 감국 추출물의 대표물질인 camphor가 갖는 지방구세포 분화억제효과를 관찰하였다. camphor의 세포독성을 확인하기 위해 3T3-L1 세포주를 이용하여 세포독성 측정을 1 day에서 10 day까지 확인하였고, 세포독성은 모두 없었다. PTCH siRNA를 처리 시 PTCH가 비활성되어 분화가 억제되었고, SMO siRNA 처리시 SMO가 비활성화되어 분화가 유도되었다. PTCH 억제는 SMO를 활성화시키는 기전으로HH 신호의 활성화가 지방구세포 분화를 억제시키는 것을 보여준다. FACS를 이용한 Gli1 발현은 KCTC 3237은 62.7±1.5%, camphor는 60.4±2.2% 로 분화된 세포 24.9±3.1% 보다 높은 것을 확인하였다. GC-MS에서 발효된 camphor의 구조변화는 없는 것으로 확인되었으나, KCTC 3237에서 15.41% 양적 증가를 확인했다. 또한camphor가 SMO를 과발현시키고, Gli1의 변화를 조절하였다. 따라서 감국 발효물의 생리활성 물질 중 향후 매커니즘 분석을 위한 활성물질인 camphor를 이용해 동물모델에서 비만억제 효과에 대한 자료가 더 필요할 것으로 여겨지며, 감국 추출물 및 발효물의 HH신호조절이 새로운 비만치료제로 개발될 수 있는 가능성을 제시하고자 한다.

• Asian Pacific Journal of Cancer Prevention
• /
• 제13권9호
• /
• pp.4607-4611
• /
• 2012

Objective: Endometrial cancer (EC) is the most common gynecologic malignancy. Identification of potential biomarkers of EC would be helpful for the detection and monitoring of malignancy, improving clinical outcomes. Methods: The Weighted Gene Co-expression Network Analysis method was used to identify prognostic markers for EC in this study. Moreover, underlying molecular mechanisms were characterized by KEGG pathway enrichment and transcriptional regulation analyses. Results: Seven gene co-expression modules were obtained, but only the turquoise module was positively related with EC stage. Among the genes in the turquoise module, COL5A2 (collagen, type V, alpha 2) could be regulated by PBX (pre-B-cell leukemia homeobox 1)1/2 and HOXB1(homeobox B1) transcription factors to be involved in the focal adhesion pathway; CENP-E (centromere protein E, 312kDa) by E2F4 (E2F transcription factor 4, p107/p130-binding); MYCN (v-myc myelocytomatosis viral related oncogene, neuroblastoma derived [avian]) by PAX5 (paired box 5); and BCL-2 (B-cell CLL/lymphoma 2) and IGFBP-6 (insulin-like growth factor binding protein 6) by GLI1. They were predicted to be associated with EC progression via Hedgehog signaling and other cancer related-pathways. Conclusions: These data on transcriptional regulation may provide a better understanding of molecular mechanisms and clues to potential therapeutic targets in the treatment of EC.

• Journal of Chest Surgery
• /
• 제50권3호
• /
• pp.153-162
• /
• 2017

Background: The mesenchymal-epithelial transition factor (MET) receptor can be overexpressed in solid tumors, including small cell lung cancer (SCLC). However, the molecular mechanism regulating MET stability and turnover in SCLC remains undefined. One potential mechanism of MET regulation involves the C-terminus of Hsp70-interacting protein (CHIP), which targets heat shock protein 90-interacting proteins for ubiquitination and proteasomal degradation. In the present study, we investigated the functional effects of CHIP expression on MET regulation and the control of SCLC cell apoptosis and invasion. Methods: To evaluate the expression of CHIP and c-Met, which is a protein that in humans is encoded by the MET gene (the MET proto-oncogene), we examined the expression pattern of c-Met and CHIP in SCLC cell lines by western blotting. To investigate whether CHIP overexpression reduced cell proliferation and invasive activity in SCLC cell lines, we transfected cells with CHIP and performed a cell viability assay and cellular apoptosis assays. Results: We found an inverse relationship between the expression of CHIP and MET in SCLC cell lines (n=5). CHIP destabilized the endogenous MET receptor in SCLC cell lines, indicating an essential role for CHIP in the regulation of MET degradation. In addition, CHIP inhibited MET-dependent pathways, and invasion, cell growth, and apoptosis were reduced by CHIP overexpression in SCLC cell lines. Conclusion: C HIP is capable of regulating SCLC cell apoptosis and invasion by inhibiting MET-mediated cytoskeletal and cell survival pathways in NCI-H69 cells. CHIP suppresses MET-dependent signaling, and regulates MET-mediated SCLC motility.