In vivo fluorescence flow cytometry reveals that the nanoparticle tumor vaccine OVA@HA-PEI effectively clears circulating tumor cells

Tumor vaccine therapy offers significant advantages over conventional treatments,including reduced toxic side effects.However,it currently functions primarily as an adjuvant treatment modality in clinical oncology due to limitations in tumor antigen selection and delivery methods.Tumor vaccines often fail to elicit a sufficiently robust immune response against progressive tumors,thereby limiting their clinical efficacy.In this study,we developed a nanoparticle-based tumor vaccine,OVA@HA-PEI,utilizing ovalbumin(OVA)as the presenting antigen and hyaluronic acid(HA)and polyethyleneimine(PEI)as adjuvants and carriers.This formulation significantly enhanced the proliferation of immune cells and cytokines,such as CD3,CD8,interferon-,and tumor necrosis factor-,in vivo,effectively activating an immune response against B16–F10 tumors.In vivofluorescenceflow cytometry(IVFC)has already become an effective method for monitoring circulating tumor cells(CTCs)due to its direct,noninvasive,and long-term detection capabilities.Our study utilized a laboratory-constructed IVFC system to monitor the immune processes induced by the OVA@HA-PEI tumor vaccine and an anti-programmed death-1(PD-1)antibody.The results demonstrated that the combined treatment of OVA@HA-PEI and anti-PD-1 antibody significantly improved the survival time of mice compared to anti-PD-1 antibody treatment alone.Additionally,this combination therapy substantially reduced the number of CTCs in vivo,increased the clearance rate of CTCs by the immune system,and slowed tumor progression.Thesefindings greatly enhance the clinical application prospects of IVFC and tumor vaccines.

Automatic detection method of bladder tumor cells based on color and shape features

Bladder urothelial carcinoma is the most common malignant tumor disease in urinary system,and its incidence rate ranks ninth in the world.In recent years,the continuous development of hyperspectral imaging technology has provided a new tool for the auxiliary diagnosis of bladder cancer.In this study,based on microscopic hyperspectral data,an automatic detection algorithm of bladder tumor cells combining color features and shape features is proposed.Support vector machine(SVM)is used to build classification models and compare the classification performance of spectral feature,spectral and shape fusion feature,and the fusion feature proposed in this paper on the same classifier.The results show that the sensitivity,specificity,and accuracy of our classification algorithm based on shape and color fusion features are 0.952,0.897,and 0.920,respectively,which are better than the classification algorithm only using spectral features.Therefore,this study can effectively extract the cell features of bladder urothelial carcinoma smear,thus achieving automatic,real-time,and noninvasive detection of bladder tumor cells,and then helping doctors improve the efficiency of pathological diagnosis of bladder urothelial cancer,and providing a reliable basis for doctors to choose treatment plans and judge the prognosis of the disease.

Celastrol activates caspase-3/GSDME-dependent pyroptosis in tumor cells by inducing endoplasmic reticulum stress Author links open overlay panel

Objective:To investigate the pyroptosis-inducing effects of celastrol on tumor cells and to explore the potential mechanisms involved,specifically focusing on the role of the caspase-3/gasdermin E(GSDME)signaling pathway and the impact of endoplasmic reticulum(ER)stress and autophagy.Methods: Necrostatin-1(Nec-1),lactate dehydrogenase release(LDH)assay,and Hoechst/propidium iodide(PI)double staining were employed to validate the mode of cell death.Western blot was used to detect the cleavage of GSDME and the expression of light chain 3(LC3)and BIP.Results: Celastrol induced cell swelling with large bubbles,which is consistent with the pyroptotic phenotype.Moreover,treatment with celastrol induced GSDME cleavage,indicating the activation of GSDME-mediated pyroptosis.GSDME knockout via CRISPR/Cas9 blocked the pyroptotic morphology of celastrol in HeLa cells.In addition,cleavage of GSDME was attenuated by a specific caspase-3 inhibitor in celastrol-treated cells,suggesting that GSDME activation was induced by caspase-3.Mechanistically,celastrol induced endoplasmic reticulum(ER)stress and autophagy in HeLa cells,and other ER stress inducers produced effects consistent with those of celastrol.Conclusion: These findings suggest that celastrol triggers caspase-3/GSDME-dependent pyroptosis via activation of ER stress,which may shed light on the potential antitumor clinical applications of celastrol.

Prognostic value of circulating tumor cells combined with neutrophil-lymphocyte ratio in patients with hepatocellular carcinoma

BACKGROUND Circulating tumor cell(CTC)count and neutrophil-to-lymphocyte ratio(NLR)are both closely associated with the prognosis of hepatocellular carcinoma(HCC).AIM To investigate the prognostic value of combining these two indicators in HCC.METHODS Clinical data were collected from patients with advanced HCC who received im-mune therapy combined with targeted therapy at the Department of Oncology,the Affiliated Hospital of Southwest Medical University,Sichuan,China,from 2021 to 2023.The optimal cutoff values for CTC programmed death-ligand 1(PD-L1)(+)>1 or CTC PD-L1(+)≤1 and NLR>3.89 or NLR≤3.89 were evaluated using X-Tile software.Patients were categorized into three groups based on CTC PD-L1(+)counts and NLR:CTC-NLR(0),CTC-NLR(1),and CTC-NLR(2).The relationship between CTC-NLR and clinical variables as well as survival rates was assessed.RESULTS Patients with high CTC PD-L1(+)expression or NLR at baseline had shorter median progression-free survival(m-PFS)and median overall survival(mOS)than those with low levels of CTC PD-L1(+)or NLR(P<0.001).Mean-while,patients in the CTC-NLR(2)group showed a significant decrease in mPFS and mOS.Cox regression analysis revealed that alpha-fetoprotein(AFP),CTC PD-L1(+),and CTC-NLR were independent predictors of OS.The time-dependent receiver operating characteristic curve showed that the area under the curve of CTC-NLR at 12 months(0.821)and 18 months(0.821)was superior to that of AFP and CTC PD-L1(+).CONCLUSION HCC patients with high CTC PD-L1(+)or NLR expression tend to exhibit poor prognosis,and a high baseline CTC-NLR score may indicate low survival.CTC-NLR may serve as an effective prognostic indicator for patients with advanced HCC receiving immunotherapy combined with targeted therapy.

Circulating tumor cells in pancreatic cancer:The prognostic impact in surgical patients

Pancreatic cancer is associated with a poor prognosis,even in the early stages,mainly due to metastatic progression.New diagnostic techniques that predict unfavorable outcomes are needed in order to improve treatment strategies.Circulating tumor cells(CTCs)are showing promising results as a predictive biomarker for various tumors.In this editorial we comment on the article by Zhang et al,who published the first systematic review and meta-analysis evaluating the prognostic value of CTCs as biomarkers in early-stage pancreatic cancer patients undergoing surgery.CTCs were detected in peripheral or central venous system blood,before or during surgery.Positive CTCs showed a correlation with decreased overall survival and decreased relapse-free,disease-free and progression-free survival in this meta-analysis.However,the heterogeneity was significant.The authors suggest that this result was related to the separation methods used between studies,but other differences such as the margin status or the neoadjuvant and adjuvant treatments used are also important to consider.CTCs may be a potential prognostic biomarker in pancreatic cancer patients,but it is necessary to compare and standardize the platforms used to isolate CTCs,to compare different biomarkers from liquid biopsy and to determine the impact on prognosis when therapeutic changes are made based on CTCs levels.

Circulating tumor cells as prognostic marker in pancreatic cancer

In this editorial we comment on the article by Zhang et al published in the recent issue of the World Journal of Clinical Oncology.Pancreatic cancer is the fourth most common cause of cancer-related mortality and has the lowest survival rate among all solid cancers.It causes 227000 deaths annually worldwide,and the 5-year survival rate is very low due to early metastasis,which is 4.6%.Cancer survival increases with better knowledge of risk factors and early and accurate diagnosis.Circulating tumor cells(CTCs)are tumor cells that intravasate from the primary tumor or metastasis foci into the peripheral blood circulation system spontan-eously or during surgical operations.Detection of CTC in blood is promising for early diagnosis.In addition,studies have associated high CTC levels with a more advanced stage,and more intensive treatments should be considered in cases with high CTC.In tumors that are considered radiologically resectable,it may be of critical importance in detecting occult metastases and preventing unnecessary surgeries.

Decreased LDHB expression in breast tumor cells causes NK cell activation and promotes tumor progression

Objective: Abnormal metabolism is the underlying reason for breast cancer progression. Decreased lactate dehydrogenase B(LDHB) has been detected in breast cancer but the function of LDHB remains unknown.Methods: Western blot was used to analyze LDHB expression in breast cancer cells. The impact of LDHB on tumor cell migration and invasion was determined using Transwell assays, wound healing assays, and a mouse lung metastasis model. Subcutaneous tumor formation, a natural killer(NK) cell cytotoxicity assay, and flow cytometry evaluated NK cell activation. Immunofluorescence and quantitative real-time PCR detected NK cell activation markers. Kaplan-Meier analysis evaluated the effect of immune cell infiltration on prognosis. Single-sample gene set enrichment analysis determined NK cell activation scores. A support vector machine predicted the role of LDHB in NK cell activation.Results: In this study we showed that LDHB inhibits the breast cancer cell metastasis and orchestrates metabolic reprogramming within tumor cells. Our results revealed that LDHB-mediated lactic acid clearance in breast cancer cells triggers NK cell activation within the tumor microenvironment. Our findings, which were confirmed in a murine model, demonstrated that LDHB in tumor cells promotes NK cell activation and ultimately results in the eradication of malignant cells. Clinically, our study further validated that LDHB affects immune cell infiltration and function. Specifically, its expression has been linked to enhanced NK cell-mediated cytotoxicity and improved patient survival. Furthermore, we identified LDHB expression in tumors as an important predictor of NK cell activation, with strong predictive ability in some cancers.Conclusions: Our results suggest that LDHB is a promising target for activating the tumor immune microenvironment in breast cancer, where LDHB-associated lactic acid clearance leads to increased NK cell activity. This study highlights the critical role of LDHB in regulating immune responses and its potential as a therapeutic target for breast cancer.

Circulating tumor cells and circulating tumor DNA in breast cancer diagnosis and monitoring

Liquid biopsy,including both circulating tumor cells and circulating tumor DNA,is becoming more popular as a diagnostic tool in the clinical management of breast cancer.Elevated concentrations of these biomarkers during cancer treatment may be used as markers for cancer progression as well as to understand the mechanisms underlying metastasis and treatment resistance.Thus,these circulating markers serve as tools for cancer assessing and monitoring through a simple,non-invasive blood draw.However,despite several study results currently noting a potential clinical impact of ctDNA mutation tracking,the method is not used clinically in cancer diagnosis among patients and more studies are required to confirm it.This review focuses on understanding circulating tumor biomarkers,especially in breast cancer.

Recent progress in aptamer-based microfluidics for the detection of circulating tumor cells and extracellular vesicles

Liquid biopsy is a technology that exhibits potential to detect cancer early,monitor therapies,and predict cancer prognosis due to its unique characteristics,including noninvasive sampling and real-time analysis.Circulating tumor cells(CTCs)and extracellular vesicles(EVs)are two important components of circulating targets,carrying substantial disease-related molecular information and playing a key role in liquid biopsy.Aptamers are single-stranded oligonucleotides with superior affinity and specificity,and they can bind to targets by folding into unique tertiary structures.Aptamer-based microfluidic platforms offer new ways to enhance the purity and capture efficiency of CTCs and EVs by combining the advantages of microfluidic chips as isolation platforms and aptamers as recognition tools.In this review,we first briefly introduce some new strategies for aptamer discovery based on traditional and aptamer-based microfluidic approaches.Then,we subsequently summarize the progress of aptamer-based microfluidics for CTC and EV detection.Finally,we offer an outlook on the future directional challenges of aptamer-based microfluidics for circulating targets in clinical applications.

Microfluidic platform for circulating tumor cells isolation and detection

Circulating tumor cells(CTCs)are essential biomarkers for liquid biopsies,which are important in the early screening,prognosis,and real-time monitoring of cancer.However,CTCs are less abundant in the peripheral blood of patients,therefore,their isolation is necessary.Recently,the use of microfluidics for CTC sorting has become a research hotspot owing to its low cost,ease of integration,low sample consumption,and unique advantages in the manipulation of micron-sized particles.Herein,we review the latest research on microfluidics-based CTC sorting.Specifically,we consider active sorting using external fields(electric,magnetic,acoustic,and optical tweezers)and passive sorting using the flow effects of cells in specific channel structures(microfiltration sorting,deterministic lateral displacement sorting,and inertial sorting).The advantages and limitations of each method and their recent applications are summarized here.To conclude,a forward-looking perspective is presented on future research on the microfluidic sorting of CTCs.

Circulating tumor cells: Biological features and survival mechanisms

Circulating tumor cells(CTCs)are neoplastic cells that are detached from primary tumors and enter circulation.Enumeration and characterization of CTCs are of significance in cancer diagnosis,prognosis,and treatment monitoring.CTC survival in the bloodstream is a limiting step for the development of metastases in distant organs.Recent technological advances,especially in single-cell molecular analyses have uncovered heterogeneous CTC survival mechanisms.Undergoing epithelial-to-mesenchymal transition(EMT),increasing stem cell-like properties,and forming cell clusters enable CTCs to adapt to the harsh microenvironment of the circulation.Expressing and releasing several immunosuppressive molecules help CTCs escape from anti-cancer immune mechanisms.This review article summarizes the biological characteristics of CTCs and focuses on the recent understanding of the mechanisms by which CTCs survive in circulation.Additionally,the clinical and therapeutic implications of CTCs are discussed.

A pilot study of the relative number of circulating tumor cells and leukocytes containing actin-binding proteins in head and neck cancer patients

Circulating tumor cells(CTCs)play an important role in tumor metastases,which is positively correlated with an increased risk of death.Actin-binding proteins,including cofilin(CFL1),profilin 1(PFN1),and adenylate cyclase-associated protein 1(CAP1),are thought to be involved in tumor cell motility and metastasis,specifically in head and neck squamous cell carcinoma(HNSCC).However,currently,there are no published studies on CFL1,PFN1,and CAP1 in CTCs and leukocytes in HNSCC patients.We assessed serum levels of CFL1,PFN1,and CAP1 and the number of CTCs and leukocytes containing these proteins in blood from 31 HNSCC patients(T1-4N0-2M0).The analysis used flow cytometry and an enzyme-linked immunosorbent assay kit.We found that CAP1+CTCs and CAP1+leukocyte subpopulations were prevalent in these HNSCC patient samples,while the prevalence rates of CFL1+and PFN1+CTCs were relatively low.Patients with stage T2-4N1-2M0 had CFL1+and PFN1+CTCs with an elevated PFN1 serum level,compared with the T1-3N0M0 group.In summary,the PFN1 serum level and the relative number of PFN1+CD326+CTCs could be valuable prognostic markers for HNSCC metastases.The current study is the first to obtain data regarding the contents of actin-binding proteins(ABPs)in CTCs,and leukocytes in blood from HNSCC patients.This is also the first to assess the relationship between the number of CTCs subgroups and disease characteristics.

Clinical implications and perspectives of portal venous circulating tumor cells in pancreatic cancer

Despite recent improvements in the diagnosis and treatment of pancreatic cancer(PC),clinical outcomes remain dismal.Moreover,there are no effective prognostic or predictive biomarkers or options beyond carbohydrate antigen 19-9 for personalized and precise treatment.Circulating tumor cells(CTCs),as a member of the liquid biopsy family,could be a promising biomarker;however,the rarity of CTCs in peripheral venous blood limits their clinical use.Because the first venous drainage of PC is portal circulation,the portal vein can be a more suitable location for the detection of CTCs.Endoscopic ultrasound-guided portal venous sampling of CTCs is both feasible and safe.Several studies have suggested that the detection rate and number of CTCs may be higher in the portal blood than in the peripheral blood.CTC counts in the portal blood are highly associated with hepatic metastasis,recurrence after surgery,and survival.The phenotypic and genotypic properties measured in the captured portal CTCs can help us to understand tumor heterogeneity and predict the prognosis of PC.Small sample sizes and heterogeneous CTC detection methods limit the studies to date.Therefore,a large number of prospective studies are needed to corroborate portal CTCs as a valid biomarker in PC.

Therapy-induced senescent tumor cells in cancer relapse

Cellular senescence is characterized by a generally irreversible cell cycle arrest and the secretion of bioactive factors known as the senescence-associated secretory phenotype(SASP).In an oncogenic context,senescence is considered a tumor suppressive mechanism as it prevents cell proliferation and inhibits the progression from pre-malignant to malignant disease.However,recent studies have demonstrated that senescent tumor cells,which could spontaneously exist within cancer tissues or arise in response to various cancer interventions(the so-called therapy-induced senescence,TIS),can acquire pro-tumorigenic properties and are capable of driving local and metastatic relapse.This highlights the complex and multifaceted nature of cellular senescence in cancer biology.Here,we summarize the current knowledge of the pathological function of therapy-induced senescent tumor cells and discuss possible mechanisms by which tumor cell senescence contributes to cancer relapse.We also discuss implications for future studies toward targeting these less appreciated cells.

Different gap junction-propagated effects on cisplatin transfer result in opposite responses to cisplatinin normal cells versus tumor cells

OBJECTIVE Previous work has shown that gap junction intercel ular communication(GJIC)enhances cisplatin(Pt)toxicity in testicular tumor cells but decreases it in non-tumor testicular cells.In this study,these different GJIC-propagated effects were demonstrated in tumor versus non-tumor cells from other organ tissues(liver and lung).METHODS We use several different mani pulations(no cell contact,pharmacological inhibition,and si RNA suppression)to down-regulate GJIC function.The in vivo results using xenograft tumor models were consistent with those from the above-mentioned cells.To better understand the mechanism(s)involved,we studied the effects of GJIC on Pt accumulation in tumor and non-tumor cells from the liver and lung.RESULTS The intracel ular Pt and DNA-Pt adduct contents clearly increased in non-tumor cells but decreasedin tumor cells when GJIC was downregulated.Further analysis indicated that the opposite effectsof GJIC on Pt accumulation in normal versus tumor cells from the liver were due to its different effects on copper transporter1 and multidrug resistance-associated protein2,membrane transporters attributed to intracellular Pt transfer.CONCLUSION GJIC protects normal organs from cisplatin toxicity while enhancing it in tumor cells via its different effects on intracellular Pt transfer.

Circulating tumor cells in pancreatic cancer patients:Enrichment and cultivation

AIM: To investigate the feasibility of separation and cultivation of circulating tumor cells (CTCs) in pancreatic cancer (PaC) using a filtration device.

Comparative study on radiosensitivity of various tumor cells and human normal liver cells

AIM:To investigate the radiation response of various human tumor cells and normal liver cells. METHODS: Cell lines of human hepatoma cells (SMMC-7721), liver cells (L02), melanoma cells (A375) and cervical tumor (HeLa) were irradiated with 60Co γ-rays. Cell survive was documented by a colony assay. Chromatid breaks were measured by counting the number of chromatid breaks and isochromatid breaks immediately after prematurely chromosome condensed by Calyculin-A. RESULTS: Linear quadratic survival curve was observed in all of four cell lines, and dose-dependent increase in radiation-induced chromatid and isochromatid breaks were observed in GB2B phase. Among these four cell lines, A375 was most sensitive to radiation, while, L02 had the lowest radiosensitivity. For normal liver cells, chromatid breaks were easy to be repaired, isochromatid breaks were difficult to be repaired. CONCLUSION: The results suggest that the y-rays induced chromatid breaks can be possibly used as a good predictor of radiosensitivity, also, unrejoined isochromatid breaks probably tightly related with cell cancerization.

Aneuploidy of chromosome 8 in circulating tumor cells correlates with prognosis in patients with advanced gastric cancer

Objective： Previous work indicated that aneuploidy of chromosome 8 in circulating tumor cells（CTCs）correlated with therapeutic efficacy for advanced gastric cancer（AGC） patients. In this follow-up study performed on the same population of AGC patients, we investigated whether and how aneuploidy of chromosome 8 in CTCs correlates with patients＇ clinical prognosis.Methods： The prospective study was performed on 31 patients with newly diagnosed AGC. Previously established integrated subtraction enrichment（SE） and immunostaining-fluorescence in situ hybridization（i FISH）platform was applied to identify, enumerate and characterize CTCs. Quantification of CTCs and analysis of their aneuploidy of chromosome 8 were performed on patients before and after therapy.Results： CTCs were measured in 93.5% of AGC patients, and two CTC subtypes with diverse threshold values were identified, multiploid CTCs with the threshold of ≥2 per 7.5 m L and multiploid plus triploid CTCs with the threshold of ≥4, which were found to significantly correlate with poor progression-free survival（PFS） and overall survival（OS）. In particular, patients with ≥10% increased multiploid CTCs after an initial 6 weeks of therapy had poor PFS and OS, whereas improved PFS and OS were observed on those who had ≥10% decreased multiploid CTCs. After adjusting for clinically significant factors, ≥10% increased post-therapy multiploid CTCs was the only independent predictor of PFS and OS.Conclusions： Aneuploidy of CTCs correlates with prognosis of AGC patients. Quantitative comparison monitoring multiploid CTCs before and after therapy may help predict improved or inferior prognosis and chemoresistance.

Internalization of NK cells into tumor cells requires ezrin and leads to programmed cell-in-cell death

Cytotoxic lymphocytes are key players in the orchestration of immune response and elimination of defective cells. We have previously reported that natural killer （NK） cells enter target tumor ceils, leading to either target cell death or self-destruction within tumor cells. However, it has remained elusive as to the fate of NK cells after internalization and whether the heterotypic cell-in-cell process is different from that of the homotypic cell-in-cell event recently named entosis. Here, we show that NK cells undergo a cell-in-cell process with the ultimate fate of apoptosis within tumor cells and reveal that the internalization process requires the actin cytoskeletal regulator, ezrin. To visualize how NK cells enter into tumor cells, we carried out real-time dual color imaging analyses of NK cell internalization into tumor cells. Surprisingly, most NK cells commit to programmed cell death after their entry into tumor cells, which is distinctively different from entosis observed in the homotypic cell-in-cell process. The apoptotic cell death of the internalized NK cells was evident by activation of caspase 3 and DNA fragmentation. Furthermore, NK cell death after internalization is attenuated by the caspase inhibitor, Z-VAD-FMK, confirming apoptosis as the mode of NK cell death within tumor cells. To determine protein factors essential for the entry of NK cells into tumor cells, we car- ried out siRNA-based knockdown analysis and discovered a critical role of ezrin in NK cell internalization. Impor- tantly, PKA-mediated phosphorylation of ezrin promotes the NK cell internalization process. Our findings suggest a novel regulatory mechanism by which ezrin governs NK cell internalization into tumor cells.

Down-regulation of Hsp90 could change cell cycle distribution and increase drug sensitivity of tumor cells

AIM:To construct Hsp90 antisense RNA eukaryotic expression vector, transfect it into SGC7901 and SGC7901/VCR of MDR-type human gastric cancer cell lines, HCC7402 of human hepatic cancer and Ec109 of human esophageal cancer cell lines, and to study the cell cycle distribution of the gene transected cells and their response to chemotherapeutic drugs.METHODS:A 1.03kb cDNA sequence of Hsp90beta was obtained from the primary plasmid phHSP90 by EcoR I and BamH I nuclease digestion and was cloned to the EcoR I and BamH I site of the pcDNA by T4DNA ligase and an antisense orientation of Hsp90beta expression vector was constructed. The constructs were transfected with lipofectamine and positive clones were selected with G418. The expression of RNA was determined with dot blotting and RNase protection assay, and the expression of Hsp90 protein determined with western blot. Cell cycle distribution of the transfectants was analyzed with flow cytometry, and the drug sensitivity of the transfectants to Adriamycin (ADR), vincrinstine (VCR), mitomycin (MMC) and cyclophosphamide (CTX) with MTT and intracellular drug concentration of the transfectants was determined with flow cytometry.RESULTS:In EcoR I and BamH I restriction analysis, the size and the direction of the cloned sequence of Hsp90beta remained what had been designed and the gene constructs were named pcDNA-Hsp90.AH-SGC7901, AH-SGC7901/VCR, AH-HCC7402 and AH-Ec109 cell clones all expressed Hsp90 anti-sense RNA. The expression of Hsp90 was down-regulated in AH-SGC7901, AH-SGC7901/VCR, AH-HCC7402 and AH-Ec109 cell clones. Cell cycle distribution was changed differently. In AH-SGC7901/VCR and AH-Ec109 cells, G(1) phase cells were increased; S phase and G(2) phase cells were decreased as compared with their parental cell lines. In AH-SGC7901 cell, G(1)phase cells were decreased, G(2) phase cells increased and S phase cells were not changed, and in AH-HCC7402 cells G(1), S and G(2) phase cells remained unchanged as compared with their parental cell lines. The sensitivity of AH-SGC7901, AH-SGC7901/VCR, AH-HCC7402 and AH-Ec109 to chemotherapeutic drugs, the sensitivity of AH-SGC7901/VCR to ADR, VCR, MMC and CTX the sensitivity of AH-HCC7402 to ADR and VCR, and the sensitivity of Ec109 to ADR, VCR and CTX all increased as compared with their parental cell lines. The mean fluorescence intensity of ADR in AH-SGC7901, AH-SGC7901/VCR, AH-HCC7402 and AH-Ec109 was also significantly elevated (P 【 0.05).CONCLUSION: Down-regulation of Hsp90 could change cell cycle distribution and increase the drug sensitivity of tumor cells.