• Journal of Cancer Prevention
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• 제22권4호
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• pp.234-240
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• 2017

Background: Lung cancer is the leading cause of cancer-related death worldwide, for which smoking is considered as the primary risk factor. The present study was conducted to determine whether genetic alterations induced by radon exposure are associated with the susceptible risk of lung cancer in never smokers. Methods: To accurately identify mutations within individual tumors, next generation sequencing was conduct for 19 pairs of lung cancer tissue. The associations of germline and somatic variations with radon exposure were visualized using OncoPrint and heatmap graphs. Bioinformatic analysis was performed using various tools. Results: Alterations in several genes were implicated in lung cancer resulting from exposure to radon indoors, namely those in epidermal growth factor receptor (EGFR), tumor protein p53 (TP53), NK2 homeobox 1 (NKX2.1), phosphatase and tensin homolog (PTEN), chromodomain helicase DNA binding protein 7 (CHD7), discoidin domain receptor tyrosine kinase 2 (DDR2), lysine methyltransferase 2C (MLL3), chromodomain helicase DNA binding protein 5 (CHD5), FAT atypical cadherin 1 (FAT1), and dual specificity phosphatase 27 (putative) (DUSP27). Conclusions: While these genes might regulate the carcinogenic pathways of radioactivity, further analysis is needed to determine whether the genes are indeed completely responsible for causing lung cancer in never smokers exposed to residential radon.

• BMB Reports
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• 제40권4호
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• pp.467-474
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• 2007

Autosomal recessive polycystic kidney disease (ARPKD) is one of the important genetic disorders in pediatric practice. Mutation of the polycystic kidney and hepatic disease gene 1 (PKHD1) was identified as the cause of ARPKD. The gene encodes a 67-exon transcript for a large protein of 4074 amino acids termed fibrocystin, but its function remains unknown. The neoplastic-like in cystic epithelial proliferation and the epidermal growth factor/epidermal growth factor receptor (EGF/EGFR) axis overactivity are known as the most important characteristics of ARPKD. Since the misregulation of $Ca^{2+}$ signaling may lead to aberrant structure and function of the collecting ducts in kidney of rat with ARPKD, present study aimed to investigate the further mechanisms of abnormal proliferation of cystic cells by inhibition of PKHD1 expression. For this, a stable PKHD1-silenced HEK-293T cell line was established. Then cell proliferation rates, intracellular $Ca^{2+}$ concentration and extracellular signal-regulated kinase 1/2 (ERK1/2) activity were assessed after treatment with EGF, a calcium channel blocker and agonist, verapamil and Bay K8644. It was found that PKHD1-silenced HEK-293T cell lines were hyperproliferative to EGF stimulation. Also PKHD1-silencing lowered the intracellular $Ca^{2+}$ and caused EGF-induced ERK1/2 overactivation in the cells. An increase of intracellular $Ca^{2+}$ in PKHD1-silenced cells repressed the EGF-dependent ERK1/2 activation and the hyperproliferative response to EGF stimulation. Thus, inhibition of PKHD1 can cause EGF-induced excessive proliferation through decreasing intracellular $Ca^{2+}$ resulting in EGF-induced ERK1/2 activation. Our results suggest that the loss of fibrocystin may lead to abnormal proliferation in kidney epithelial cells and cyst formation in ARPKD by modulation of intracellular $Ca^{2+}$.

• 대한암한의학회지
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• 제23권1호
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• pp.23-32
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• 2018

ALK 변이는 비소세포성 폐암에서 차지하는 비율은 높지 않지만 비소세포성 폐암의 발생률이 높기 때문에 환자 수는 적지 않다. ALK 저해제인 Crizotinib은 환자들의 무진행 생존을 평균 대략 4개월 정도 연장시키고 증상을 완화시키며 항암 치료를 받는 것에 비교하여 삶의 질을 향상시키는 치료성과를 거두었다. 하지만 약물 내성 발현은 주요 한계이며 여전히 ALK 변이 비소세포성 폐암 환자의 예후가 불량하므로 내성을 극복하고 지속적인 치료 반응을 유도하여 치료율을 상승시키기 위한 연구가 필요하다. 현재 폐암치료 한약제제인 삼칠충초정과 2세대 EGFR TKI 제제인 Afatinib의 동시 사용 시 상승효과가 나타난다는 연구결과는 보고되어 있지만 ALK 저해제인 Crizotinib과의 병용 치료와 관련한 연구는 시행된 바가 없었다. 본 증례는 삼칠충초정과 Crizotinib의 병용 투여를 통해 종양 크기의 불변 및 삶의 질 개선과 Crizotinib의 내성 억제 가능성 등을 보인 점에서 의의가 있으나 대조군이 없는 1례에 불과하여 Crizotinib의 단독 효과일 가능성을 배제할 수 없는 한계를 지닌다. 따라서 향후 삼칠충초정과 Crizotinib의 병용투여에 대한 추가적인 연구 및 임상시험을 통해 더욱 객관적인 효과 판정이 필요할 것으로 사료된다.

• Molecular & Cellular Toxicology
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• 제5권3호
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• pp.193-197
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• 2009

Suppressors of cytokine signaling (SOCS) proteins were originally identified as negative feedback regulators of cytokine signaling and include the Janus kinase/Signal transducer and activator of transcription (JAK/STAT) pathways. Recent studies have shown that SOCS proteins negatively regulate the receptor tyrosine kinase (RTK) pathway including the insulin receptor (IR), EGFR, and KIT signaling pathways. In addition, SOCS1 and SOCS3 have been reported to have anti-tumor effects in human hepatocellular carcinoma (HCC). However, it is uncertain whether other members of the SOCS family are associated with tumor development and progression. In this study, to investigate whether SOCS6 is aberrantly regulated in HCC, we examined the expression level of SOCS6 in HCC by Western blot analysis and immunohistochemical staining. The results showed that SOCS6 was down-regulated in all examined HCCs compared to the corresponding normal tissues. In addition, expression of SOCS6 was observed in the cytoplasm of most normal and precancerous tissue, but not in the HCCs by immunohistochemical staining. This is first report to demonstrate that SOCS6 is aberrantly regulated in HCC. These findings suggest that underexpression of SOCS6 is involved in hepatocarcinogenesis, and SOCS6 may play a role, as a tumor suppressor, in HCC development and progression.

• Tuberculosis and Respiratory Diseases
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• 제63권1호
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• pp.42-51
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• 2007

배 경: 폐암의 새로운 치료제로 각광을 받고 있는 TRAIL은 암에 선택적으로 apoptosis를 일으킨다고 알려진 cytokine으로 알려져 있다. 또한 gefitinib (Iressa)는 폐암의 적용된 최초의표적치료제로 각광을 받고 있다. 그러나 일부의 암세포에서는 이에 대한 저항성을 보이고 있다. 본 연구에서는 암세포에서 외부의 apoptotic 자극에 저항성을 보이는 IGF-1R를 억제함으로 TRAIL 및 gefitinib의 항암작용을 증가시키고자 실험을 시행하였다. 방 법: 암세포주는 TRAIL 및 gefitinib에 민감한 NCI H460와 두 약제에 중등도의 저항성을 보이는 A549의 폐암세포주로 시행하였으며 IGF-1R의 억제는 본 연구자가 개발하였던 IGF-1 pathway를 dominant negative inhibition을 할 수 있는 adenovirus- IGF1R(482 ST, 950ST) 및 IGF-1R tyrosine kinase inhibitor인 Tyrphostin AG1024를 사용하였고 gefitinib에 대한 실험에서는 RNA interference를 이용하여 IGF-1R의 발현을 억제하는 adenovirus- shIGF-1R을 이용하였다. 결 과: TRAIL에 저항성을 보이는 폐암세포주(A549)에서 adenovirus-IGF1R(482ST, 950ST) 및 AG1024로 IGF-1R를 억제한 후 TRAIL을 투여한 경우 항암효과가 증대되었다. A549에 adenovirus- shIGF-1R을 감염시켜 IGF-1R의 발현을 억제한 결과 gefitinib에 대한 감수성이 증가되었다.

• 대한수의학회지
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• 제43권2호
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• pp.211-218
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• 2003

Human ovarian cancerous cells survive in a way that they trigger the nucleotide excision repair (NER) or double-strand DNA repair (dsDNA) repair mechanism to show resistance to anticancer drugs and activate many kinds of repair protein, thus removing damaged DNAs. Two experiments on the PA-1 human ovarian teratocareinoma cell line that hardly has any expression of epidermal growth factor receptor (EGFR) were conducted in the study; first, EGF-R was transfected and its receptor was obtained. The receptor was investigated in terms of its mutual relations with many kinds of protein concerning NER or dsDNA repair. Second, it was examined what kind impact cisplatin and adriamycin had on the effects of EGF-R over the PA-1 cell line lacking EGF-R. When being administered with cisplatin and adriamycin, Hey and Hey C2 cell lines showed a high level of resistance while PA-1 cell line a high level of sensitivity. Hey and Hey C2 cell lines that are resistant against anticancer drugs exhibited a high level of EGF-R expression while PA-1 cell line that is sensitive to them did a much lower level of the expression. When PA-1 cell line was transfected for the expression of DNA adduct and EGF-R, it showed a higher level of resistance compared to the control group. There was no difference in the expression of DNA repair proteins (DNA- dependent protein kinase, Ku70, and Ku80) between Hey and the PA-1 cell lines. The results indicate that the Hey cell line that is resistant against cisplatin and adriamycin works along the signaling system responding to the changes of EGF-R while the PA-1 cell line that is sensitive to both of them does to the lack of EGF-R.

• Asian Pacific Journal of Cancer Prevention
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• 제13권12호
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• pp.6155-6157
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• 2012

Background: Mutations in the MAPK (Mitogen Activated Protein Kinase) signaling pathway - EGFR/Ras/RAF/MEK have been associated with the development of several carcinomas. ERK2, a downstream target of the MAPK pathway and a founding member of the MAPK family is activated by cellular signals emanating at the cell membrane. Activated ERK2 translocates into the nucleus to transactivate genes that promote cell proliferation. MKP - a dual specific phosphatase - interacts with activated ERK2 via the common docking (CD) domain of the later to inactivate (dephosphorylate) and effectively terminate further cell proliferation. A constitutively active form of ERK2 carrying a single point mutation - E322K in its CD domain, was earlier reported by our laboratory. In the present study, we investigated the prevalence of this CD domain E322K mutation in 88 well differentiated OSCC tissue samples. Materials and Method: Genomic DNA specimens isolated from 88 oral squamous cell carcinoma tissue samples were amplified with primers flanking the CD domain of the ERK2 gene. Subsequently, PCR amplicons were gel purified and subjected to direct sequencing to screen for mutations. Results: Direct sequencing of eighty eight OSCC samples identified an E322K CD domain mutation in only one (1.1%) OSCC sample. Conclusions: Our result indicates that mutation in the CD domain of ERK2 is rare in OSCC patients, which suggests the role of genetic alterations in other mitogenic genes in the development of carcinoma in the rest of the patients. Nevertheless, the finding is clinically significant, as the relatively rare prevalence of the E322K mutation in OSCC suggests that ERK2, being a common end point signal in the multi-hierarchical mitogen activated signaling pathway may be explored as a viable drug target in the treatment of OSCC.

• Asian Pacific Journal of Cancer Prevention
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• 제15권5호
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• pp.1961-1970
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• 2014

Pyruvate kinase isozyme type M2 (PKM2) was first found in hepatocellular carcinoma (HCC), and its expression has been thought to correlate with prognosis. A large number of studies have demonstrated that epithelial-mesenchymal transition (EMT) is a crucial event in hepatocellular carcinoma (HCC) and associated metastasis, resulting in enhanced malignancy of HCC. However, the roles of PKM2 in HCC EMT and metastasis remain largely unknown. The present study aimed to determine the effects of PKM2 in EGF-induced HCC EMT and elucidate the molecular mechanisms in vitro. Our results showed that EGF promoted EMT in HCC cell lines as evidenced by altered morphology, expression of EMT-associated markers, and enhanced invasion capacity. Furthermore, the present study also revealed that nuclear translocation of PKM2, which is regulated by the ERK pathway, regulated ${\beta}$-catenin-TCF/LEF-1 transcriptional activity and associated EMT in HCC cell lines. These discoveries provide evidence of novel roles of PKM2 in the progression of HCC and potential therapeutic target for advanced cases.

• Asian Pacific Journal of Cancer Prevention
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• 제13권3호
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• pp.909-914
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• 2012

Background: Gefitinib, a tyrosine kinase inhibitor (TKI) of epidermal growth factor receptor (EGFR), is used both as a single drug and concurrently with whole brain radiotherapy (WBRT) the standard treatment for brain metastases (BM), and is reported to be effective in a few small studies of patients with BM from non-small-cell lung cancer (NSCLC). However, no study has compared the two treatment modalities. This retrospective analysis was conducted to compare the efficacy of gefitinib alone with gefitinib plus concomitant WBRT in treatment of BM from NSCLC. Methods: We retrospectively reviewed 90 patients with BM from NSCLC who received gefitinib alone (250mg/day, gefitinib group) or with concomitant WBRT (40Gy/20f/4w, gefitinib-WBRT group) between September 2005 and September 2009 at Sun Yat-Sen University Cancer Center. Forty-five patients were in each group. Results: The objective response rate of BM was significantly higher in gefitinib-WBRT group (64.4%) compared with gefitinib group (26.7%, P<0.001). The disease control rate of BM was 71.1% in gefitinib-WBRT group and 42.2% in gefitinib group (P=0.006). The median time to progression of BM was 10.6 months in gefitinib-WBRT group and 6.57 months in gefitinib group (P<0.001). The median overall survival(OS) of gefitinib-WBRT and gefitinib alone group was 23.40 months and 14.83 months, respectively (HR, 0.432, P=0.002). Conclusion: Gefitinib plus concomitant WBRT had higher response rate of BM and significant improvement in OS compared with gefitinib alone in treatment of BM from NSCLC.

• Annals of Pediatric Endocrinology and Metabolism
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• 제23권4호
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• pp.204-209
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• 2018

Purpose: Growth hormone transduction defect (GHTD) is characterized by severe short stature, impaired STAT3 (signal transducer and activator of transcription-3) phosphorylation and overexpression of the cytokine inducible SH2 containing protein (CIS) and p21/CIP1/WAF1. To investigate the role of p21/CIP1/WAF1 in the negative regulation of the growth hormone (GH)/GH receptor and Epidermal Growth Factor (EGF)/EGF Receptor pathways in GHTD. Methods: Fibroblast cultures were developed from gingival biopsies of 1 GHTD patient and 1 control. The protein expression and the cellular localization of p21/CIP1/WAF1 was studied by Western immunoblotting and immunofluorescence, respectively: at the basal state and after induction with $200-{\mu}g/L$ human GH (hGH) (GH200), either with or without siRNA CIS (siCIS); at the basal state and after inductions with $200-{\mu}g/L$ hGH (GH200), $1,000-{\mu}g/L$ hGH (GH1000) or 50-ng/mL EGF. Results: After GH200/siCIS, the protein expression and nuclear localization of p21 were reduced in the patient. After successful induction of GH signaling (control, GH200; patient, GH1000), the protein expression and nuclear localization of p21 were reduced. After induction with EGF, p21 translocated to the cytoplasm in the control, whereas in the GHTD patient it remained located in the nucleus. Conclusion: In the GHTD fibroblasts, when CIS is reduced, either after siCIS or after a higher dose of hGH (GH1000), p21's antiproliferative effect (nuclear localization) is also reduced and GH signaling is activated. There also appears to be a positive relationship between the 2 inhibitors of GH signaling, CIS and p21. Finally, in GHTD, p21 seems to participate in the regulation of both the GH and EGF/EGFR pathways, depending upon its cellular location.