• Journal of Life Science
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• v.34 no.10
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• pp.744-754
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• 2024

Cancer cells exhibit a unique metabolic process for uncontrolled cell division, providing bioenergy and intermediates, which are significantly different from normal cells. Here an aerobic glycolysis converts most of the pyruvate produced from glucose into lactate and inefficiently produced ATP. Cancer cells counter their lack of energy through glutamine metabolism, together with glucose. Glutamine is the most abundant amino acid in the blood and is used for the synthesis of amino acids, nucleotides, and lipids, as well as bioenergy through glutaminolysis. Cancer cells rely on glutamine rather than normal cells, showing more than half of the tricarboxylic acid cycle metabolites derived from glutamine, called glutamine addiction. Oncogenes c-Myc also regulates the expression of various genes involved in glutamine metabolism and promotes the absorption of glutamine. Whether glutaminase (GLS) causes or inhibits tumors is controversial. However, GLS1 is a promising treatment target due to its higher carcinogenic incidence, whereas GLS2 is known to act as a tumor suppressor. The 4th-generation metabolic anti-cancer therapy, which has been actively investigated since the mid-2010s, is based on a complex and sophisticated network of cancer metabolites. These drugs directly regulate the energy metabolism of cancer cells to maximize anti-cancer effects without side effects. GLS is a crucial enzyme for cancer metabolism and tumor progression that catalyzes the first stage in the process of glutaminolysis. The development of anti-cancer drugs targeting GLS enzymes has emerged as a promising strategy.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.11
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• pp.4637-4642
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• 2014

Background: Hypoxia-inducible factor $1{\alpha}$ (HIF-$1{\alpha}$) plays an important role in regulating cell survival and angiogenesis, which are critical for tumor growth and metastasis. Genetic variations of HIF1A have been shown to influence the susceptibility to many kinds of human tumors. Increased expression of HIF-$1{\alpha}$ has also been demonstrated to be involved in tumor progression. However, the prognostic value of single nucleotide polymorphisms (SNPs) inthe HIF1A gene remains to be determined in most cancer types, including colorectal cancer (CRC). In this study, we sought to investigate the predictive role of HIF1A SNPs in prognosis of CRC patients and efficacy of chemotherapy. Materials and Methods: We genotyped two functional SNPs in HIF1A gene using the Sequenom iPLEX genotyping system and then assessed their associations with clinicopathological parameters and clinical outcomes of 697 CRC patients receiving radical surgery using Cox logistic regression model and Kaplan Meier curves. Results: Generally, no significant association was found between these 2 SNPs and clinical outcomes of CRC. In stratified analysis of subgroup without adjuvant chemotherapy, patients carrying CT/TT genotypes of rs2057482 exhibited a borderline significant association with better overall survival when compared with those carrying CC genotype [Hazard ratio (HR), 0.47; 95% confidence interval (95% CI): 0.29-0.76; P < 0.01]. Moreover, significant protective effects on CRC outcomes conferred by adjuvant chemotherapy were exclusively observed in patients carrying CC genotype of rs2057482 and in those carrying AC/CC genotype of rs2301113. Conclusions: Genetic variations in HIF1A gene may modulate the efficacy of adjuvant chemotherapy after surgery in CRC patients.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.3
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• pp.1715-1720
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• 2013

Background: The discovery that microRNAs (miRNAs) regulate proliferation, invasion and metastasis provides a principal molecular basis of tumor heterogeneity. Microvessel distribution is an important characteristic of solid tumors, with significant hypoxia occurring in the center of tumors with low blood flow. The distribution of miR-374a in breast tumors was examined as a factor likely to be important in breast cancer progression. Methods: Breast tissue samples from 40 patients with breast cancer were classified into two groups: a highly invasive and metastatic group (HIMG) and a low-invasive and metastatic Group (LIMG). Samples were collected from the center and edge of each tumor. In each group, six specimens were examined by microRNA array, and the remaining 14 specimens were used for real-time RT-qPCR, Western blot and immunohistochemical analyses. Correlation analysis was performed for the miRNAs and target proteins. Follow-up was carried out during 28 months to 68 months after surgery, and survival data were analyzed. Results: In the LIMG, the relative content of miR-374a was lower in the center of the tumor than at its edge; in the HIMG, it was lower at the edge of the tumor, and miR-374a levels were lower in breast cancer tissues than in normal tissues. There was no difference between VEGF-A and VCAM-1 mRNA levels at the edge and center of the tumor; however, we observed a significant difference between VEGF-A and VCAM-1 protein expression levels in these two regions. There was a negative correlation between miR-374a and target protein levels. The microvessel density (MVD) was lower in the center of the tumor than at its edge in HIMG, but the LIMG vessels were uniformly distributed. There was a significant positive correlation between MVD and the number of lymph node metastases (Pearson correlation, r=0.912, P<0.01). The median follow-up time was 48.5 months. LIMG had higher rate of disease-free survival (100%, P=0.013) and longer median survival time (66 months) than HIMG, which had a lower rate of 75% and shorter median survival time (54 months). Conclusions: Our data demonstrated miR-374a to be differentially distributed in breast cancer; VEGF-A and VCAM-1 mRNA had coincident distribution, and the distribution of teh respective proteins was uneven and opposite to that for the miR-374a. These data might explain the differences in the distribution of MVD in breast cancer and variation in breast cancer prognosis.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.3
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• pp.1889-1894
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• 2013

Background: Basaloid squamous cell carcinoma of the esophagus (BSCCE) is a rare and distinctive tumor with no standard treatment. This study aimed to explore treatment in relation to prognosis of the disease. Methods: A total of 142 patients with BSCCE that underwent treatment in our hospital from March 1999 to July 2010 were retrospectively analyzed. All patients received surgery, 42 postoperative radiotherapy and 28 patients chemotherapy. Results: There were 26 patients included in stage I, 60 in stage II, 53 in stage III and 3 in stage IV. The clinical symptoms and macroscopic performances of BSCCE did not differ from those of typical esophageal squamous cell carcinoma. Among 118 patients receiving endoscopic biopsy, only 12 were diagnosed with BSCCE. The median survival time (MST) of the entire group was 32 months, with 1-, 3- and 5-year overall survival (OS) of 81.4%, 46.8% and 31.0%, respectively. The 5-year OS of stage I and II patients was significantly longer than that of stages III/IV, at 60.3%, 36.1% and 10.9%, respectively (p<0.001, p=0.001). The MST and 5-year OS were 59.0 months and 47.4% in patients with tumors located in the lower thoracic esophagus, and 27.0 months and 18.1% in those with lesions in the upper/middle esophagus (p=0.002). However, the survival was not significantly improved in patients undegoing adjunctive therapy. Multivariate analysis showed TNM stage and tumor location to be independent prognostic factors. Furthermore, distant metastasis was the most frequent failure pattern, with a median recurrence time of 10 months. Conclusion: BSCCE is an aggressive disease with rapid progression and a propensity for distant metastasis. It is difficult to make a definitive diagnosis via preoperative biopsy. Multidisciplinary therapy including radical esophagectomy with extended lymphadenectomy should be recommended, while the effectiveness of radiochemotherapy requires further validation for BSCCE.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.20
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• pp.8893-8900
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• 2014

Dysregulated expression of microRNAs (miRNAs) has been shown to be closely associated with tumor development, progression, and carcinogenesis. However, their clinical implications for gastric cancer remain elusive. To investigate the hypothesis that genome-wide alternations of miRNAs differentiate gastric cancer tissues from those matched adjacent non-tumor tissues (ANTTs), miRNA arrays were employed to examine miRNA expression profiles for the 5-pair discovery stage, and the quantitative real-time polymerase chain reaction (qRTPCR) was applied to validate candidate miRNAs for 48-pair validation stage. Furthermore, the relationship between altered miRNA and clinicopathological features and prognosis of gastric cancer was explored. Among a total of 1,146 miRNAs analyzed, 16 miRNAs were found to be significantly different expressed in tissues from gastric cancer compared to ANTTs (p<0.05). qRT-PCR further confirmed the variation in expression of miR-193b and miR-196a in the validation stage. Down-expression of miR-193b was significantly correlated with Lauren type, differentiation, UICC stage, invasion, and metastasis of gastric cancer (p<0.05), while over-expression of miR-196a was significantly associated with poor differentiation (p=0.022). Moreover, binary logistic regression analysis demonstrated that the UICC stage was a significant risk factor for down-expression of miR-193b (adjusted OR=8.69; 95%CI=1.06-56.91; p=0.043). Additionally, Kaplan-Meier survival curves indicated that patients with a high fold-change of down-regulated miR-193b had a significantly shorter survival time (n=19; median survival=29 months) compared to patients with a low fold-change of down-regulated miR-193b (n=29; median survival=54 months) (p=0.001). Overall survival time of patients with a low fold-change of up-regulated miR-196a (n=27; median survival=52 months) was significantly longer than that of patients with a high fold-change of up-regulated miR-196a (n=21; median survival=46 months) (p=0.003). Hence, miR-193b and miR-196a may be applied as novel and promising prognostic markers in gastric cancer.

• Journal of Applied Biological Chemistry
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• v.57 no.2
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• pp.103-111
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• 2014

A1E is an extract from traditional Asian medicinal plants that has therapeutic activities against cancers, metabolic disease, and other intractable conditions. However, its mechanism of action on cervical cancer has not been studied. In order to ascertain if A1E would have pronounced anti-cervical cancer effect, cervical cancer cells were incubated with A1E and apoptosis was detected by nuclear morphological changes, annexin V-FITC/PI staining, cell cycle analysis, western blotting, Reverse-transcription polymerase chain reaction, and measurement of mitochondrial membrane potential. Expression of human papiloma virus E6 and E7 oncogenes was down-regulated in A1E-treated cervical cancer cells, while p53 and retinoblastoma protein levels were enhanced. A1E also perturbed cell cycle progression at sub-G1 and altered cell cycle regulatory factors in SiHa cervical cancer cells. A1E activated apoptotic intrinsic pathway markers such as caspase-9, caspase-3 and poly ADP-ribose polymerase, and down-regulated expression of Bcl-2 and Bcl-xl. A1E induced mitochondrial membrane potential collapse and cytochrome c release, and inhibited phosphatidylinositol 3-kinase (PI3K)/Akt, key factors involved in cell survival signaling. Taken all these results, A1E induced apoptosis via activation of the intrinsic pathway and inhibition of the PI3K/Akt survival-signaling pathway in SiHa cervical cancer cells. In conclusion, A1E exerts anti-proliferative action growth inhibition on cervical cancer cells through apoptosis which demonstrates its anti-cervical cancer properties.

• Journal of Life Science
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• v.33 no.12
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• pp.978-986
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• 2023

Inflammation by the innate immune system is a protective mechanism of the organism against infection-mediated environmental factors. It is also responsible for the pathogenesis of various human diseases, including the progression of cancer. Lichens are receiving increasing attention as a source of bioactive molecules with therapeutic potential for a variety of diseases. Additionally, the antioxidant, anti-inflammatory, and anticancer potential of lichen and its secondary metabolites have been widely reported. However, the underlying mechanism is still unknown. In the present study, to investigate molecular mechanisms of anti-inflammation and anti-cancer activity in the Antarctic lichen, Usnea aurantiaco-atra, methanol extract of Usnea aurantiaco-atra (MEUS) was used in vitro assays in RAW 264.7 macrophages cell and HCT116 colon cancer cells. Based on our data, MEUS had the anti-inflammatory activity through the modulation of main inflammatory indicators such as COX-2, IL-6, iNOS, TNF-α and NO production in a concentration-dependent manner. In addition, we observed that MEUS had cytotoxic activity against HCT116 colon cancer cells in a concentration-dependent manner, leading to a significantly reduced proliferation of the cancer cells through apoptotic induction by activating caspase-3. Taken together, this work firstly reported the anti-inflammatory and anti-cancer activities of an Antarctic lichen, Usnea aurantiaco-atra, and MEUS may provide a new insight into the molecular mechanisms underlying a link between inflammation and cancer.

• Journal of Physiology & Pathology in Korean Medicine
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• v.17 no.1
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• pp.213-219
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• 2003

We investigated the effects of Insamsapye-tang (ISSPT) water extract on the cell proliferation of human lung carcinoma A549 cells. ISSPT treatment resulted in the inhibition of cell proliferation in a concentration-dependent manner. This anti-proliferative effect of A549 cells by ISSSPT treatment was associated with morphological changes such as membrane shrinking and cell rounding up. DNA flow cytometric histograms showed that population of G1 phase of the cell cycle was increased by ISSPT treatment in a concentration-dependent manner. ISSPT treatment induced the levels of tumor suppressor p53 protein and cyclin-dependent kinase (Cdk) inhibitor p27 without significant alteration of cyclins and Cdks expression. In addition, ISSPT treatment resulted in down-regulation of phosphorylated retinoblastoma protein (pRB). However, the levels of p130, the pRB family protein, and transcription factors. E2F-1 and E2F-4. were remained unchanged. The present results indicated that ISSPT-induced inhibition of lung cancer cell proliferation is associated with the blockage of G1/S progression and the induction of apoptosis, and we suggest that ISSPT will be an effective therapeutic agent on human lung cancer.

• Preventive Nutrition and Food Science
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• v.21 no.1
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• pp.31-37
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• 2016

Opuntia humifusa (OHF) has been used as a nutraceutical source for the prevention of chronic diseases. In the present study, the inhibitory effects of ethyl acetate extracts of OHF on the proliferation of AGS human gastric cancer cells and the mode of action were investigated. To elucidate the antiproliferative mechanisms of OHF in cancer cells, the expression of genes related to apoptosis and cell cycle arrest were determined with real-time PCR and western blot. The cytotoxic effect of OHF on AGS cells was observed in a dose-dependent manner. Exposure to OHF ($100{\mu}g/mL$) significantly induced (P<0.05) the G1 phase cell cycle arrest. Additionally, the apoptotic cell population was greater (P<0.05) in OHF ($200{\mu}g/mL$) treated AGS cells when compared to the control. The expression of genes associated with cell cycle progression (Cdk4, Cdk2, and cyclin E) was significantly downregulated (P<0.05) by the OHF treatment. Moreover, the expression of Bax and caspase-3 in OHF treated cells was higher (P<0.05) than in the control. These findings suggest that OHF induces the G1 phase cell cycle arrest and activation of mitochondria-mediated apoptosis pathway in AGS human gastric cancer cells.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.4
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• pp.2413-2419
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• 2013

Background: Use of epidermal growth factor receptor inhibitors (EGFR-TKIs ) is now standard for non-small-cell lung cancer (NSCLC). However, the effects of EGFR-TKIs in maintenance therapy for advanced NSCLC patients are still unclear. The preent meta-analysis was performed to examine pooled data of randomized control trials (RCT) where EGFR-TKIs were compared against placebo in maintenance regimens for patients with advanced NCSLC to quantify potential benefits and determine safety. Methods: Several data bases were searched, including PubMed, EMBASE and CENTRAL, and we performed an internet search of conference literature. The endpoints were objective response rates (ORR), progression-free survival (PFS) and overall survival (OS). We performed a meta-analysis of the published data, using Comprehensive Meta Analysis software (Version 2.0). with a fixed effects model and an additional random effects model, when applicable. The results of the meta-analysis are expressed as hazard ratios (HRs) or risk ratios (RRs), with their corresponding 95% confidence intervals (95%CIs). Results: The final analysis included six trials, covering 3,758 patients. Compared with placebo, EGFR-TKIs maintenance therapy improved ORR and PFS for patients with advanced NSCLC, the difference being statistically significant (P<0.05), but proved unable to prolong patients' OS. The main adverse reactions were diarrhea and rashes. Conclusion: EGFR-TKIs demonstrated encouraging efficacy, safety and survival when delivered as maintenance therapy for patients with advanced NSCLC after first-line chemotherapy, especially for the patients who had adenocarcinomas, were female, non-smokers and patients with EGFR gene mutations.