The prognostic impact of immune checkpoint inhibitors for the treatment of pulmonary sarcomatoid carcinoma: A multicenter retrospective study.

Pulmonary sarcomatoid carcinoma (PSC) is an aggressive and poorly differentiated type of non-small cell lung carcinoma. Because of the rarity of PSC, the efficacy and toxicity of immunotherapy remain unclear. Hence, the aim of this study was to evaluate the efficacy and safety of immune checkpoint inhibitors (ICIs) for the treatment of advanced PSC. The study cohort was limited to 33 patients with pathologically confirmed PSC treated with ICIs in four hospitals in China from March 2018 to March 2022. Expression of programmed death ligand 1 (PD-L1) was detected by immunohistochemical analysis. Categorical variables were compared with the Fisher exact test and survival analysis was conducted with the Kaplan-Meier method. Of the 33 PSC patients, 8 (24.2%) received monotherapy with ICIs and 25 (75.8%) received combination therapy with ICIs. The objective response rate (ORR) and disease control rate (DCR) were 36.4% and 78.8%, respectively. The median durations of progression-free survival (PFS) and overall survival (OS) were 6.07 and 21.33 months, respectively. PD-L1 status in 16 available samples was assessed, which included 30.3% PD-L1-positive patients. The ORRs for PD-L1-positive vs. -negative patients were 50.0% and 90.0%, the DCR was 33.3% and 83.3%, and the median PFS was 17.50 and 6.07 months, respectively (p=0.812). The median OS was not reached in PD-L1-positive and -negative patients (p=0.655). The incidence of immune-related adverse (irAEs) was 48.5% and mainly included grade 1 or 2 (39.4%), while the incidence of grade 3 or 4 was 9.1%. Pneumonia (9.1%) and skin rash (9.1%) were the most frequent irAEs. Immunotherapy with ICIs was a promising regimen to improve the prognosis of patients with advanced PSC.

Efficacy and safety of apatinib as second or later-line therapy in extensive-stage small cell lung cancer: a prospective, exploratory, single-arm, multi-center clinical trial.

Background: A paucity of strategies exist for extensive-stage small cell lung cancer (ES-SCLC) patients who fail the first-line chemotherapy. Apatinib is a tyrosine kinase inhibitor (TKI) that selectively inhibits vascular endothelial growth factor receptor-2 (VEGFR-2), which has been demonstrated to have active anti-tumor activity in ES-SCLC when used only or combined with PD-1 inhibitors or chemotherapy with good tolerance. However, the efficacy and safety of apatinib monotherapy is unclear in second-line or beyond treatment of ES-SCLC. Methods: In this prospective, exploratory, single-arm, multi-center study, eligible patients were aged 18 years or older with histologically confirmed ES-SCLC, and had progressed on, or were intolerant to previous systemic treatment. Patients received apatinib 500 mg (orally qd, every 4 weeks a cycle). The efficacy was assessed after 1 cycle and then every 2 cycles based on computed tomography imaging per the Response Evaluation Criteria in Solid Tumors (RECIST, version 1.1). The primary endpoint was progression-free survival (PFS). The adverse events (AEs) were assessed per the National Cancer Institute Common Terminology Criteria for Adverse Events 4.0 (NCI-CTCAE 4.0). This study is registered in the Chinese Clinical Trial Registry, number ChiCTR-OPC-17013964. Results: From 28 July 2017 to 21 June 2019, 62 patients were screened for eligibility, among whom 57 patients were available for efficacy and safety analysis. The objective response rate (ORR) was 14.3% and disease control rate (DCR) was 79.6%. The median PFS was 5.6 months [95% confidence interval (CI): 3.3-8.0 months] and the median overall survival (OS) was 11.2 months (95% CI: 7.5-24.0 months). Among the participants who received apatinib as second-line treatment, the median PFS and OS were 6.1 months (95% CI: 2.6-7.6 months) and 12.0 months (95% CI: 7.9 months to not reached), respectively. The most common AEs of all grades were anemia (36.8%), hypertension (33.3%), fatigue (31.6%), blood bilirubin increased (22.8%), elevated transaminase (19.3%), and hand-foot syndrome (17.54%). Grade 3 AEs included 2 (3.5%) cases of hypertension and 1 (1.8%) case of fatigue. No grade 4/5 AEs were observed. Conclusions: Apatinib showed encouraging anti-tumor activity in pretreated ES-SCLC patients with tolerable toxicities. Further larger scale studies are warranted to demonstrate the efficacy of apatinib.

Pemetrexed-based chemotherapy for non-small-cell lung cancer patients with EGFR exon 20 insertion mutation: a multicenter study.

BACKGROUND: Chemotherapy is the major choice for advanced non-small-cell lung cancer (NSCLC) patients with epidermal growth factor receptor exon 20 insertion (EGFR ex20ins). The efficacy of pemetrexed-based with other chemotherapy regimens and EGFR ex20ins subtypes in this population has not been well studied. METHODS: We screened patients with EGFR ex20ins by next-generation sequencing (NGS) from a large cohort. The clinicopathologic and medical information were collected in advanced NSCLC patients with EGFR ex20ins. We also compared the clinical outcomes among patients with different subtypes of EGFR ex20ins. RESULTS: We retrospectively collected 119 stage IIIB/IV NSCLC patients with EGFR ex20ins from 9142 NSCLC patients across China from June 2013 to December 2018. The subtypes of EGFR ex20ins included A767_V769dupASV (33/119, 27.73%), S768_D770dupSVD (19/119, 15.97%), N771_H773dupNPH (11/119, 9.24%), A763_Y764insFQEA (2/119, 1.68%) and others (54/119, 45.38%). A total of 64.7% (77/119) of patients received pemetrexed-based first-line chemotherapy and 13.45% (16/119) of patients received pemetrexed-based second-line chemotherapy. Pemetrexed-based chemo-treated patients had longer median progression-free survival (PFS) than patients without pemetrexed-based chemo-treated (5.5 vs. 3.0 months, P=0.0026). Survival data was available for 66 patients and the median overall survival (OS) was 24.7 months. Pemetrexed-based chemo-treated patients had longer OS tendency than patients without pemetrexed-based chemo-treated (25.0 vs. 19.6 months, P=0.0769). Patients harboring A767_V769dupASV had better OS than other subtypes of EGFR ex20ins but without statistical significance (P=0.0676). Multivariate analysis revealed that histological type of NSCLC and bone-metastasis before treatment were independent prognostic factors for OS in all patients after adjusting all characteristic and treatment factors (P<0.05). CONCLUSIONS: To the best of our knowledge, it is the largest cohort study of advanced NSCLC patients with EGFR ex20ins across China. Pemetrexed-based treatment could have better control of disease than non-pemetrexed-based chemotherapies in this population. Furthermore, more effective agents are expected for patients harboring EGFR ex20ins.

Association between BRAF mutant classification and the efficacy of pemetrexed-based chemotherapy in Chinese advanced non-small cell lung cancer patients: a multicenter retrospective study.

BACKGROUND: BRAF mutation plays a rare but aggressive oncogenic role in non-small cell lung cancer (NSCLC) patients. The controversy of first-line chemotherapy in patients with different BRAF mutations exists. Here, we identified 41 stage IIIB/IV NSCLC patients with BRAF mutation from 3,669 NSCLC patients by next-generation sequencing (NGS) testing of ctDNA in plasma or tumor tissues. METHODS: Kaplan-Meier survival curves were used to compare the prognostic difference of progression-free survival (PFS) and overall survival (OS) in different classes of BRAF mutations. Multivariate Cox proportional-hazards regression was used to determine the hazard ratio (HR) of different prognostic factors in survival. RESULTS: A total of 40 stage IIIB/IV NSCLC patients with BRAF mutation were further divided into four groups according to the updated functional classification of BRAF mutations, 56.1% (23/41) of class 1, 12.2% (5/41) of class 2, 12.2% (5/41) of class 3 and 19.5% (8/41) of others. The median PFS of patients after first-line pemetrexed-based chemotherapy was longer than other regimens of chemotherapy (7.0 vs. 4.0 months, P<0.001). The patients with class 1 BRAF mutation treated with pemetrexed-based first-line chemotherapy had a better OS than other regimens of chemotherapy (30 vs. 22 months, P<0.001). A significant improvement of OS was observed in patients with class 1 BRAF mutation than other groups (25 vs. 12, 15 and 14 months, P<0.0001). Multivariate analysis showed that first-line pemetrexed-based chemotherapy was associated with better PFS and OS (HR =0.16 and 0.31, respectively; P<0.001 and 0.02, respectively), as well as improved OS in patients with class 1 BRAF mutation than other classes (HR =2.15, P<0.001). CONCLUSIONS: Pemetrexed-based regimen could be considered as first-line chemotherapy in advanced NSCLC patients with BRAF mutants when target therapy is unavailable, especially in patients harboring class 1 mutations compared with other classes.

ATP triggered drug release and DNA co-delivery systems based on ATP responsive aptamers and polyethylenimine complexes.

Stimuli-responsive nanocarriers for anticancer drug and gene co-delivery are a promising strategy in cancer therapy due to their combination of chemotherapy and gene therapy. In this work, we developed a facile and effective method to fabricate stimuli-responsive nanocarriers for anticancer drug and gene co-delivery based on complexes of polyethylenimine (PEI) with an adenosine triphosphate (ATP) responsive aptamer duplex (ARAD). No chemical reactions or complex modifications were used in the construction processes. In this system, Doxorubicin-loaded aptamer duplex and plasmid DNA (p53) can be bound by PEI by electronic interactions to form stable complexes which effectively protect the aptamer and p53 from DNase degradation. The intercalated Dox can be released on-demand by a structural change in the aptamer duplex in an ATP-rich environment. The morphology and average size of the nanocarriers were characterized by zeta potential and transmission electron microscopy (TEM). The nanocarriers exhibit lower cell toxicity in HeLa cell lines relative to PEI. RT-PCR and Western blot analysis confirmed that p53 could be effectively delivered and expressed in HeLa cells by PEI/ARAD/p53 complexes. Moreover, the apoptosis percentage of HeLa cells treated with PEI/ARAD/Dox/p53 complex increased to 40.8%, compared to 24.7% for PEI/ARAD/Dox complex and 11.5% for PEI/ARAD/p53, respectively. The result demonstrated that the combinatorial delivery of Dox and p53 by nanocarriers could induce synergistic actions and lead to effective cancer cell apoptosis.

Association of miR-146a gene polymorphism with risk of nasopharyngeal carcinoma in the central-southern Chinese population.

This case-control study focused on estimating the association between miR-146a polymorphism and risk of nasopharyngeal carcinoma (NPC) in central-south China. In total, 160 patients with NPC and 200 healthy controls in central-south China were genotyped using polymerase chain reaction-restriction fragment length polymorphism assay. Chi-square test was used to assess the different distribution of miR-146a polymorphism between NPC patients and controls; and logistic regression analysis was applied to analyze the associations between miR-146a polymorphism with cancer risk in different contrast models. Significant differences between NPC patients and controls were found in genotype (P=0.033 for GG versus CG versus CC; and odds ratio (OR)=0.568, 95% confidence interval (CI)=0.354-0.912, P=0.019 for CG versus CC; and OR=0.503, 95% CI=0.261-0.971, P=0.041 for CG versus CC; and OR=0.564, 95% CI=0.360-0.884, P=0.012 for GG+CG versus CC, respectively) and allelic analysis (P=0.025 for G versus C). Our findings suggested that polymorphism of mir-146a was associated with NPC in the central-southern Chinese population.

Association between PIN1 promoter polymorphisms and risk of nasopharyngeal carcinoma.

Peptidylprolyl cis/trans isomerase, NIMA-interacting 1 (PIN1) plays an important role in cell transformation and oncogenesis. Association between PIN1 promoter polymorphisms and cancer risk was reported in several cancers. This study aimed to evaluate the association between two single nucleotide polymorphisms (SNPs, -667T>C, rs2233679 and -842G>C, rs2233678) on PIN1 promoter and risk of nasopharyngeal carcinoma (NPC). The two SNPs were genotyped using polymerase chain reaction-restriction fragment length polymorphism in a total of 334 native Chinese subjects consisting of 178 cases and 156 controls. The results indicated that the -667CT heterozygote and -667CC homozygote exhibited a significantly decreased risk of nasopharyngeal carcinoma when compared with -667TT homozygote (OR = 0.639, 95% CI = 0.452-0.903, p = 0.011 for -667CT; and OR = 0.441, 95% CI = 0.213-0.915, p = 0.038 for -667CC, respectively). In the -842G>C polymorphism, compared with -842GG homozygote, only -842CG heterozygote but not -842CC homozygote had a significantly decreased risk of nasopharyngeal carcinoma (OR = 0.465, 95% CI = 0.249-0.871, p = 0.010). Genotype in the two SNPs in patients showed no significant associations with the clinicopathologic features examined. Our study showed that the minor genotypes of PIN1 promoter (-667CT, -667CC and -842CG) were associated with decreased risk of NPC in a Chinese population, suggested that PIN1 promoter polymorphisms might play an important role in NPC carcinogenesis.

Association study between miR-149 gene polymorphism and nasopharyngeal carcinoma.

Association studies between single-nucleotide polymorphism (SNP) rs2292832 on miR-149 gene and cancer risk have been previously analyzed in several types of cancer. The aim of this study was to evaluate the association between miR-149 polymorphism and risk of nasopharyngeal carcinoma (NPC). miR-149 gene polymorphism was genotyped using polymerase chain reaction (PCR)-restriction fragment length polymorphism (RFLP) in 158 patients with NPC and 242 healthy individuals. Associations with cancer risk and clinicopathological characteristics were analyzed by χ2 test. No significant difference was observed for miR-149 gene polymorphism in NPC patients and healthy controls in either genotype (P=0.427 for CC vs. CT vs. TT, P=0.247 for CT vs. TT and P=0.323 for CC vs. TT, respectively) or allelic analysis (P=0.216). No significant difference was noted between the genotypes and the clinicopathological parameters examined with the exception of clinical stage. A significantly higher CC distribution in clinical stage I-II compared with III-IV was observed under the dominant model (CC vs. CT vs. TT, P=0.026) and the co-dominant model (CC vs. TT, P=0.030). The results of this study suggested that the CC genotype of miR-149 contributes to the progression and development, rather than the initiation of NPC.

p63 Expression is a prognostic factor in colorectal cancer.

p63 is highly expressed in some malignant tumors and is associated with tumorigenesis, invasion and metastasis. The aim of our study was to evaluate the clinical significance of p63 in colorectal cancer (CRC). p63 expression was detected by immunohistochemistry in 66 CRC patients. Correlations between p63 expression and clinicopathological factors, progression-free survival (PFS) and overall survival (OS) were analyzed. Among the 66 CRC cases, 31 cases (47%) exhibited a high score of p63 expression, while 35 cases (53%) were marked with a low score. The p63 level correlated with peritumoral deposits (p=0.021). The 5-year OS rates in the low p63 score and high p63 score groups were, respectively, 49% and 74% (p<0.001). The 5-year PFS rates in the low p63 score and high p63 score groups were, respectively, 44% and 71% (p<0.001). Univariate analysis revealed that p63 expression was correlated with OS and PFS. Multivariate analysis suggested that p63 expression was an independent prognostic factor for OS (p=0.035). In conclusion, p63 was negatively correlated with peritumoral deposits and positively associated with OS and PFS in CRC. The data suggest that p63 is a potential prognostic factor for CRC.

Circulating miR-221 directly amplified from plasma is a potential diagnostic and prognostic marker of colorectal cancer and is correlated with p53 expression.

BACKGROUND AND AIM: Circulating miRNAs exist in serum and plasma and they can be used as a potential noninvasive molecular marker for colorectal cancer (CRC) diagnosis. The present study was to test the availability of direct amplification of miRNAs from plasma without RNA extraction, and to evaluate its clinical application value in CRC. METHODS: Plasma miR-21, miR-221 and miR-222 levels were determined in 103 CRC patients and 37 healthy normal controls by quantitative reverse transcription-polymerase chain reaction. Immunohistochemical staining for p53, carcinoembryonic antigen (CEA), estrogen receptor (ER) and progesterone receptor (PR) was carried out in the same CRC patient cohort. The correlation between miR-221 levels and protein levels of p53, CEA, ER and PR, clinicopathological features or overall survival was analyzed. RESULTS: A standard curve shows a good linearity between the log of sample input and C(T) values over three orders of magnitude of plasma miR-21, miR-221 and miR-222. ROC curve analysis reveals that the plasma levels of miR-221 is a potential biomarker for differentiating CRC patients from controls. Kaplan-Meier curve assessment shows that the elevated plasma miR-221 level is a significant prognostic factor for poor overall survival in CRC patients. The immunohistochemistry analysis demonstrates a significant correlation between plasma miR-221 level and p53 expression. CONCLUSIONS: The direct amplification of plasma miR-221 can be used as a potential noninvasive molecular marker for diagnosis and prognosis of CRC and is correlated with p53 expression.

5-Fluorouracil upregulates the activity of Wnt signaling pathway in CD133-positive colon cancer stem-like cells.

BACKGROUND AND OBJECTIVE: CD133-positive colon cancer stem like cells (CSLCs) are resistant to the conventional cytotoxic drug 5-fluorouracil (5-FU). Wnt signaling pathway plays important roles in colon cancer carcinogenesis and metastasis, and regulates the self-renewal capacity of CSLCs. In the present study, we explored the impact of 5-FU on Wnt signaling pathway of CD133-positive colon CSLCs, and the relation between Wnt signaling pathway and drug resistance of CD133-positive colon CSLCs. METHODS: Magnetic activation cell separation was used to collect CD133-positive cells from colon cancer cell line DLD1, which was transfected with luciferase reporter for Wnt signaling activity. The activity of Wnt signaling pathway was compared between CD133-positive and CD133-negative cells. After the treatment with 1 µg/mL of 5-FU, the cell proliferation rates of DLD1 cells, CD133-positive cells, and CD133-negative cells were compared. After the treatment with 1 µg/mL and 10 µg/mL of 5-FU for 48 h, Wnt activity was compared between CD133-positive and CD133-negative cells. The expression of CD133 and cell apoptosis of CD133-positive cells was detected after exposure to 50 ng/mL of dickkopf (DKK)-1, a Wnt pathway inhibitor. RESULTS: After the treatment with 5-FU, the cell proliferation rate of CD133-positive cells was higher than that of CD133-negative cells and the sensitivity of CD133-positive cells to 5-FU decreased. Wnt activity was higher in CD133-positive cells than in CD133-negative cells [(46.3 ± 0.3)% vs. (33.9 ± 2.7)%, P = 0.009]. After the treatment with 1 µg/mL and 10 µg/mL of 5-FU, Wnt activity of CD133-positive cells was (90.1 ± 10.0)% (P = 0.012) and (52.9 ± 2.5)% (P = 0.047), respectively, whereas that of CD133-negative cells was (35.5 ± 3.3)% (P = 0.434) and (26.5 ± 0.4)% (P = 0.046), respectively. CD133 expression in CD133-positive cells decreased from (87.2 ± 5.3)% to (60.6 ± 3.1)% (P = 0.022) after treatment with DKK-1, whereas the cell apoptosis rate increased from (11.8 ± 0.2)% to (28.3 ± 0.6)% (P = 0.013). CONCLUSIONS: Wnt activity is higher in CD133-positive DLD1 cells than in CD133-negative DLD1 cells. 5-FU can upregulate Wnt activity of CD133-positive colon CSLCs. Blocking Wnt activity may reverse drug sensitivity of CD133-positive cells to 5-FU.

The role of Skp2 in extranodal NK/T-cell lymphoma.

BACKGROUND AND OBJECTIVE: Expression of Skp2 was related with the prognosis of several tumors. However, there was no intensive study on the relationship between Skp2 and extranodal NK/T cell lymphoma. This study was to explore the role of Skp2 in extranodal NK/T cell lymphoma. METHODS: The clinicopathological data of 39 patients with extranodal NK/T cell lymphoma were analyzed. The expression of Skp2 was examined by immunohistochemistry on formalin fixed, paraffin embedded tissue sections. RESULTS: Among the patients with high expression of Skp2, complete remission (CR) rate was only 14.3% (2/14). However, CR rate among the patients with low expression of Skp2 was 68.0% (17/25). Significant difference was shown between these two groups (P < 0.001). In the group of low expression, the median overall survival (OS) was 85.59 months (95% CI: 35.83 135.34 months), the 1 and 2 year OS rates were 81% and 71%, respectively. However, in the group of high expression, the median OS was only 9.73 months (95% CI: 2.05-17.40 months), the 1 and 2 year OS rates were 42% and 14%, respectively. There was statistical difference between these two groups (P < 0.001). Multivariate analysis showed that Skp2 expression (P <0.001), LDH (P = 0.026) and ECOG PS (P = 0.003) were dependent prognostic factors of extranodal NK/T cell lymphoma. CONCLUSION: High expression of Skp2 is an independent unfavorite adverse prognostic factor of extranodal NK/T cell lymphoma.

Diagnostic and prognostic value of circulating miR-221 for extranodal natural killer/T-cell lymphoma.

Extra-nodal natural killer T-Cell (NK/T-cell) lymphoma is a progressive cancer with poor prognosis due to the lack of disease specific treatment. To develop specific therapeutic strategies, it is essential to identify tumor markers. Recent studies show that circulating microRNA (miRNA) may serve as diagnostic and/or prognostic markers for some diseases. To explore miRNAs as potential diagnostic and/or prognostic markers of NK/T-cell lymphoma, in our study, we compared circulating miR-221 levels in 79 patients and 37 normal subjects by real-time PCR amplification directly from plasma samples, and correlated patient's miR-221 levels with their clinic features and treatment outcomes. We observed a significant difference between the patient and control groups (p=0.038), and a correlation of plasma miR-221 level in patient with sex, as well as a reverse correlation with performance status and the overall survival after treatment. Univariate and multivariate analyses further revealed that plasma miR-221 level, age, B symptoms, LDH level and complete response after primary treatment all present prognostic values when judged by overall survival (OS). Together, our results show that it is feasible to perform direct amplification of plasma miRNAs without total RNA extraction, and plasma miR-221 may be a diagnostic and prognostic marker for NK/T-cell lymphoma.

[Effect of KRAS mutation on efficacy of Cetuximab combined with chemotherapy in advanced colorectal cancer patients].

OBJECTIVE: To explore the relationship between KRAS gene status and efficacy of Cetuximab (C225) combined with chemotherapy on advanced colorectal cancer in Chinese patients, and to evaluate the safety of C225. METHODS: From May 2006 to March 2009, 81 patients with advanced colorectal cancer received Cetuximab combined with chemotherapy were enrolled in this study. The rate of KRAS mutation and the relationship of KRAS with response rate (RR), progression-free survivor (PFS), overall survival (OS) and adverse reaction of C225 were analyzed retrospectively. RESULTS: All the 81 patients received C225 therapy, and the overall RR was 33.3%. The RR of initiate therapy was 57.1%; of the second line and over the third line therapy was 38.5% and 22.0% respectively. KRAS gene phenotype examination was performed in 44 patients whose tumor samples were available. KRAS mutation was found in 20 cases (45%). Out of 44 patients, 43 were evaluable for response. RR was 5% and 43.48% in KRAS mutation and wild KRAS patients respectively (P =0.002). The median PFS was 7.0 weeks and 18.6 weeks in mutational KRAS patients and wild KRAS patients, reaching statistical significance (P =0.003). The median OS was 15.2 months and 17.3 months in mutational KRAS patients and wild KRAS patients respectively without statistical significance (P =0.463). The common adverse reactions were leucopenia, nausea, vomiting and rash. All the adverse reactions were tolerated. The incidence of skin rash in patients with mutational KRAS and patients without KRAS mutation was 40% and 42% respectively, without statistical significance (P =0.91). CONCLUSION: C225 combined with chemotherapy is well-tolerated in Chinese patients with advanced colorectal cancer, and it can significantly prolong PFS of patients with wild KRAS as compared to patients with KRAS mutation.

[In vitro inhibitory effect of dibenzoxanthene CY-B12 on proliferation of tumor cell lines and its possible mechanisms].

BACKGROUND & OBJECTIVE: CY-B12, a new dibenzon-xanthene, has been synthesized recently. This study was to investigate the in vitro antiproliferative activity of CY-B12 and its possible mechanisms. METHODS: The inhibitory effects of CY-B12 on proliferation of gastric carcinoma cell line MGC803, nasopharyngeal carcinoma cell line CNE-2, oral epithelial carcinoma cell line KB-3-1, and lung cancer cell line Glc82 were assessed by MTT assay. Cell cycle distribution and apoptosis were detected by flow cytometry (FCM). Apoptotic morphology of CNE-2 cells was observed under fluorescent microscope after Hoechst33258 staining. The expression of cell cycle-related proteins Cdc25C, Cdc2, and Cyclin B1 were measured by Western blot. DNA damage was detected by single cell gel electrophoresis (SCGE). RESULTS: CY-B12 obviously inhibited the proliferation of MGC803, CNE-2, KB-3-1, and Glc82 cells; the IC(50) values were 7.51, 9.58, 8.84, and 15.99 micromol/L, respectively. After treatment of CY-B12, CNE-2 cells were arrested at G(2)/M phase; chromatin condensation, apoptotic bodies, and sub-G1 peak were observed in CNE-2 cells. The protein expression of Cdc25C in CNE-2 cells was down-regulated by CY-B12 in a dose-dependent mannerû whereas Cyclin B1 and Cdc2 were up-regulated by low dose of CY-B12, and down-regulated by high dose of CY-B12. CY-B12 induced DNA damage in CNE-2 cells in a dose-dependent manner. CONCLUSION: CY-B12 has potent in vitro antiproliferative activity, which may be exerted through breaking DNA, down-regulating cell cycle-related protein Cdc25C, and inducing cell cycle arrest and apoptosis.