Betamethasone transdermal administration combined with fractional Er:YAG lasers or microplasma radiofrequency technology improved hypertrophic scars: A retrospective study.

OBJECTIVE: This retrospective study aims to compare the efficacy rates in treating hypertrophic scars among four distinct groups of patients who either underwent fractional Erbium: yttrium-aluminum-garnet (Er:YAG) laser or microplasma radiofrequency technology as standalone treatments or in combination with compound betamethasone transdermal administration. METHOD: The study retrospectively examined 208 patients treated at our institution from April 2011 to December 2022 for hypertrophic scars, receiving no less than three treatments (with an interval of 8 weeks between each). The patients were categorized into four groups: the F group (treated with fractional Er:YAG laser), the F + B group (treated with fractional Er:YAG laser combined with compound betamethasone transdermal administration), the P group (treated with microplasma radiofrequency technology), and the P + B group (treated with microplasma radiofrequency technology combined with compound betamethasone transdermal administration). The therapeutic effects were evaluated based on the changes in the Vancouver Scar Scale (VSS) scores before and after treatment in these groups. RESULTS: There was no statistically significant difference in the VSS scores among the four groups before treatment. After undergoing three sessions of the aforementioned four types of treatment, all groups showed a decrease in VSS scores, with average posttreatment VSS scores for the F group scored 5.15 ± 2.084, F + B group scored 3.7 ± 1.781, P group scored 4.41 ± 1.933, and P + B group scored 3.16 ± 1.775, respectively. With an increasing number of treatments, the total effective rate gradually increased in all four groups, and the combination treatment using compound betamethasone transdermal administration proved more effective than the standalone treatment. CONCLUSION: All four treatments yielded favorable outcomes, with the combined therapy involving compound betamethasone transdermal administration proving more effective than the standalone treatments, meriting further clinical attention.

Identification of splicing factors signature predicting prognosis risk and the mechanistic roles of novel oncogenes in HNSCC.

Head and neck squamous cell carcinoma (HNSCC) is the most frequent subtype of head and neck cancer, generally with a poor prognosis and limited therapeutic options due to its highly heterogeneous malignancy. In this study, we screened functional splicing regulatory RNA binding proteins (RBPs) that were closely related with the prognosis of HNSCC patients and showed significant expression differences between HNSCC tumors and normal tissues. Based on this finding, we chose six candidate genes (HNRNPC, ZCRB1, RBM12B, SF3A2, SF3B3, and SRSF11) to generate a prognostic prediction model and validated the accuracy of the prognostic model for predicting patient survival outcomes. We found that the risk score predicted by our model can serve as an independent prognostic predictor. Notably, HNSCC tumors showing higher expression of SF3B3, HNRNPC, or ZCRB1 possessed higher risk scores in the discovered prediction model. The investigation of the underlying mechanism validated that knockdown of SF3B3, HNRNPC, and ZCRB1 separately induced a substantial impairment of HNSCC cell survival. Conversely, overexpression of each of the three genes promoted tumor cellular proliferation. High throughput RNA sequencing analysis revealed that changes in the expression of SF3B3 and HNRNPC remarkably affected alternative splicing of genes related to cell cycle regulation, whereas the depletion of ZCRB1 contributed to aberrant splicing events involving in DNA damage response. In addition, the prognostic prediction model's risk score was demonstrated to be related with the immune infiltration score. Particularly, SF3B3 has a negative correlation with CD8A expression. Therefore, our findings provide promising prognosis predictors and potential therapeutic targets for better treatment efficacy of HNSCC.

Epigenetics: Novel crucial approach for osteogenesis of mesenchymal stem cells.

Bone has a robust regenerative potential, but its capacity to repair critical-sized bone defects is limited. In recent years, stem cells have attracted significant interest for their potential in tissue engineering. Applying mesenchymal stem cells (MSCs) for enhancing bone regeneration is a promising therapeutic strategy. However, maintaining optimal cell efficacy or viability of MSCs is limited by several factors. Epigenetic modification can cause changes in gene expression levels without changing its sequence, mainly including nucleic acids methylation, histone modification, and non-coding RNAs. This modification is believed to be one of the determinants of MSCs fate and differentiation. Understanding the epigenetic modification of MSCs can improve the activity and function of stem cells. This review summarizes recent advances in the epigenetic mechanisms of MSCs differentiation into osteoblast lineages. We expound that epigenetic modification of MSCs can be harnessed to treat bone defects and promote bone regeneration, providing potential therapeutic targets for bone-related diseases.

Targeting SKA3 suppresses the proliferation and chemoresistance of laryngeal squamous cell carcinoma via impairing PLK1-AKT axis-mediated glycolysis.

Spindle and kinetochore-associated complex subunit 3 (SKA3) is a well-known regulator of chromosome separation and cell division, which plays an important role in cell proliferation. However, the mechanism of SKA3 regulating tumor proliferation via reprogramming metabolism is unknown. Here, SKA3 is identified as an oncogene in laryngeal squamous cell carcinoma (LSCC), and high levels of SKA3 are closely associated with malignant progression and poor prognosis. In vitro and in vivo experiments demonstrate that SKA3 promotes LSCC cell proliferation and chemoresistance through a novel role of reprogramming glycolytic metabolism. Further studies reveal the downstream mechanisms of SKA3, which can bind and stabilize polo-like kinase 1 (PLK1) protein via suppressing ubiquitin-mediated degradation. The accumulation of PLK1 activates AKT and thus upregulates glycolytic enzymes HK2, PFKFB3, and PDK1, resulting in enhancement of glycolysis. Furthermore, our data reveal that phosphorylation at Thr360 of SKA3 is critical for its binding to PLK1 and the increase in glycolysis. Collectively, the novel oncogenic signal axis "SKA3-PLK1-AKT" plays a critical role in the glycolysis of LSCC. SKA3 may serve as a prognostic biomarker and therapeutic target, providing a potential strategy for proliferation inhibition and chemosensitization in tumors, especially for LSCC patients with PLK1 inhibitor resistance.

Crosstalk between RNA m6A Modification and Non-coding RNA Contributes to Cancer Growth and Progression.

N6-methyladenosine (m6A) is the most common RNA modification and has an important role in normal development and tumorigenesis. The abnormal expression of m6A regulators can lead to an imbalance in m6A levels in cancer cells, leading to the dysregulated expression of oncogenes and tumor suppressor genes that may contribute to cancer development, patient response to chemoradiotherapy, and clinical prognosis. Recent studies demonstrate that non-coding RNAs are involved in epigenetic modification of both DNA and RNA in tumor cells, and may also affect the development and progression of cancer by targeting m6A regulators. In this review, we describe the functional crosstalk between m6A and non-coding RNAs, particularly microRNA, long non-coding RNA, and circular RNA, and illustrate their roles in tumor regulation. Finally, we discuss the significance of non-coding RNA and m6A modification in the diagnosis, treatment, and prognosis of cancer patients, as well as potential future research directions.

Circular RNA circCORO1C promotes laryngeal squamous cell carcinoma progression by modulating the let-7c-5p/PBX3 axis.

BACKGROUND: Laryngeal squamous cell carcinoma (LSCC) is a common malignant tumor of the head and neck. LSCC patients have seriously impaired vocal, respiratory, and swallowing functions with poor prognosis. Circular RNA (circRNA) has attracted great attention in cancer research. However, the expression patterns and roles of circRNAs in LSCC remain largely unknown. METHODS: RNA sequencing was performed on 57 pairs of LSCC and matched adjacent normal mucosa tissues to construct circRNA, miRNA, and mRNA expression profiles. RT-PCR, qPCR, Sanger sequencing, and FISH were undertaken to study the expression, localization, and clinical significance of circCORO1C in LSCC tissues and cells. The functions of circCORO1C in LSCC were investigated by RNAi-mediated knockdown, proliferation analysis, EdU staining, colony formation assay, Transwell assay, and apoptosis analysis. The regulatory mechanisms among circCORO1C, let-7c-5p, and PBX3 were investigated by luciferase assay, RNA immunoprecipitation, western blotting, and immunohistochemistry. RESULTS: circCORO1C was highly expressed in LSCC tissues and cells, and this high expression was closely associated with the malignant progression and poor prognosis of LSCC. Knockdown of circCORO1C inhibited the proliferation, migration, invasion, and in vivo tumorigenesis of LSCC cells. Mechanistic studies revealed that circCORO1C competitively bound to let-7c-5p and prevented it from decreasing the level of PBX3, which promoted the epithelial-mesenchymal transition and finally facilitated the malignant progression of LSCC. CONCLUSIONS: circCORO1C has an oncogenic role in LSCC progression and may serve as a novel target for LSCC therapy. circCORO1C expression has the potential to serve as a novel diagnostic and prognostic biomarker for LSCC detection.

Non-coding RNAs in drug resistance of head and neck cancers: A review.

Head and neck cancer (HNC), which includes epithelial malignancies of the upper aerodigestive tract (oral cavity, oropharynx, pharynx, hypopharynx, larynx, and thyroid), are slowly but consistently increasing, while the overall survival rate remains unsatisfactory. Because of the multifunctional anatomical intricacies of the head and neck, disease progression and therapy-related side effects often severely affect the patient's appearance and self-image, as well as their ability to breathe, speak, and swallow. Patients with HNC require a multidisciplinary approach involving surgery, radiation therapy, and chemotherapeutics. Chemotherapy is an important part of the comprehensive treatment of tumors, especially advanced HNC, but drug resistance is the main cause of poor clinical efficacy. The most important determinant of this phenomenon is still largely unknown. Recent studies have shown that non-coding RNAs have a crucial role in HNC drug resistance. In addition, they can serve as biomarkers in the diagnosis, treatment, and prognosis of HNCs. In this review, we summarize the relationship between non-coding RNAs and drug resistance of HNC, and discuss their potential clinical application in overcoming HNC chemoresistance.

miR-424-5p Promotes Proliferation, Migration and Invasion of Laryngeal Squamous Cell Carcinoma.

BACKGROUND: Recent studies revealed that miR-424-5p regulates the malignant behavior of multiple cancer types. However, the expression and function of miR-424-5p in laryngeal squamous cell carcinoma (LSCC) is unclear. PURPOSE: This study aimed to evaluate the association of miR-424-5p level with clinical features of LSCC and investigate the effect and potential mechanism of miR-424-5p on LSCC progression. METHODS: The expression of miR-424-5p in LSCC and paired adjacent normal margin (ANM) tissues from 106 patients with LSCC were analyzed by quantitative PCR (qPCR), and clinical significance was analyzed. Target genes of miR-424-5p were predicted, followed by functional annotation. The functional role of miR-424-5p in LSCC was investigated by molecular and cellular experiments with LSCC cell lines, with flow cytometry used for cell cycle analysis. In addition, miR-424-5p regulation of the predicted target gene cell adhesion molecule 1 (CADM1) was validated by qPCR, Western blot analysis and luciferase reporter assay. RESULTS: miR-424-5p was upregulated in LSCC versus ANM tissues. High miR-424-5p level was significantly associated with poor differentiation, advanced tumor stage and cervical lymph node metastasis. Bioinformatics analysis showed that miR-424-5p target genes are mainly enriched in biological processes of the cell cycle, cell division, and negative regulation of cell migration, and were involved in multiple cancer-related pathways. Overexpression of miR-424-5p promoted proliferation, migration, invasion, and adhesion of LSCC cells and affected the cell cycle progression. Additionally, CADM1 was a direct target of miR-424-5p in LSCC cells. CONCLUSION: miR-424-5p functions as an oncogene to promote the aggressive progression of LSCC, and CADM1 is a direct downstream target of miR-424-5p in LSCC cells. miR-424-5p may be a potential therapeutic target in LSCC.

Identification of miR-145-5p-Centered Competing Endogenous RNA Network in Laryngeal Squamous Cell Carcinoma.

This study intends to investigate the transcriptional regulatory role of miR-145-5p in laryngeal squamous cell carcinoma (LSCC). LSCC cell line TU-177 is transfected with miR-145-5p mimics, generating miR-145-5p-overexpression LSCC cells. Whole transcriptome microarrays are used to investigate the differentially expressed lncRNAs, circRNAs, mRNAs, and miRNAs. The target genes of miRNAs are predicted and performed functional annotation. Additionally, the circRNAs, lncRNAs, and mRNAs that interact with miRNAs are predicted, and then the competing endogenous RNAs (ceRNAs) are predicted. Microarray analysis identifies 26 miRNAs, 248 mRNAs, 1118 lncRNAs, and 382 circRNAs differentially expressed in miR-145-5p overexpressed LSCC cells. Overall, 675 target genes are identified for the differentially expressed miRNAs, which involved in cell adhesion associated gene ontology (GO) terms, and MAPK and FoxO signaling pathways. The up-regulated mRNAs involved in the pathway of ABC transporters, while the down-regulated mRNAs involved in pathway of olfactory transduction. Moreover, 149 ceRNAs are predicted, which are associated with apoptosis, Wnt pathway, and metabolic pathway. Furthermore, qPCR results confirm that miR-145-5p affects expression of lncRNAs, miRNAs, mRNAs, and circRNAs in LSCC cells. Collectively, miR-145-5p may be inhibits LSCC progression via ceRNA-mediated pathways, such as WNT2B-miR-145-5p-NONHSAT127539.2, CASP10-miR-145-5p-NONHSAT127539.2, CASP10-miR-145-5p-circ_0003519, and TPO-miR-145-5p-circ_0003519.

Astragali radix total flavonoid synergizes cisplatin to inhibit proliferation and enhances the chemosensitivity of laryngeal squamous cell carcinoma.

Laryngeal squamous cell carcinoma (LSCC) is the most common head and neck cancer. Astragali radix extracts play crucial roles in the regulation of cancer progression. However, the role of Astragali radix extracts in LSCC and the related mechanisms remains unclear. Here, we evaluated the inhibitory effects of the combined use of Astragali radix total flavonoid (TFA) and cisplatin (CDDP) on an LSCC mouse model by pharmacodynamics. Ultra-high-performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS) was employed to define the prototype of TFA in vivo. The potential drug targets were identified through the integrative analysis of LSCC microarrays, RNA sequencing data and the main bioactive component of TFA. Furthermore, a protein-protein interaction network, compound-target network and target-pathway network were constructed based on the prototype and potential drug targets to identify the main targets and pathways. Animal experiments showed that TFA has significant synergistic antitumor activity with cisplatin and attenuates the nephrotoxicity caused by CDDP chemotherapy, improving the survival of LSCC-bearing mice. Using UPLC-MS/MS, we identified 8 constituents of TFA in experimental mice serum: formononetin, ononin, calycosin, calycosin-7-O-ß-D-glucoside, 7,2'-dihydroxy-3',4'-dimethoxyisoflavan, 7,2'-dihydroxy-3',4'-dimethoxyisoflavaneglucoside, 3-hydroxy-9,10-dimethoxypterocarpan and 9,10-dimethoxyptercarpan-3-O-ß-d-glucoside. Integrative analysis predicted 19 target genes for TFA constituents, and the target genes were mainly involved in the EGFR-related cancer signaling, metabolism and oxidative stress. Collectively, these findings highlight the role of TFA in the regulation of LSCC and provide potential targets for a high-efficiency and low-toxicity therapeutic strategy of LSCC.

Promoter Methylation-Regulated miR-145-5p Inhibits Laryngeal Squamous Cell Carcinoma Progression by Targeting FSCN1.

Laryngeal squamous cell carcinoma (LSCC) is a common form of head and neck cancer with poor prognosis. However, the mechanism underlying the pathogenesis of LSCC remains unclear. Here, we demonstrated increased expression of fascin actin-bundling protein 1 (FSCN1) and decreased expression of microRNA-145-5p (miR-145-5p) in a clinical cohort of LSCC. Luciferase assay revealed that miR-145-5p is a negative regulator of FSCN1. Importantly, low miR-145-5p expression was correlated with TNM (tumor, node, metastasis) status and metastasis. Moreover, cases with low miR-145-5p/high FSCN1 expression showed poor prognosis, and these characteristics together served as independent prognostic indicators of survival. Gain- and loss-of-function studies showed that miR-145-5p overexpression or FSCN1 knockdown inhibited LSCC migration, invasion, and growth by suppressing the epithelial-mesenchymal transition along with inducing cell-cycle arrest and apoptosis. Additionally, hypermethylation of the miR-145-5p promoter suggested that repression of miR-145-5p arises through epigenetic inactivation. LSCC tumor growth in vivo could be inhibited by using miR-145-5p agomir or FSCN1 small interfering RNA (siRNA), which highlights the potential for clinical translation. Collectively, our findings indicate that miR-145-5p plays critical roles in inhibiting the progression of LSCC by suppressing FSCN1. Both miR-145-5p and FSCN1 are important potential prognostic markers and therapeutic targets for LSCC.

Evaluation of the therapeutic effect of micro-plasma radio frequency on hypertrophic scars in rabbit ears.

To evaluate the therapeutic effect of micro-plasma radio frequency on hypertrophic scars in rabbit ears to provide an experimental basis and theoretical foundation for the treatment of hypertrophic scars. Hypertrophic scars were established on the ventral surface of the ears of six New Zealand white rabbits. Left and right ears were randomly divided into two groups: experimental group treated with micro-plasma radio frequency and control group with no treatment. H&E staining and CD34 labeling of microvessels were performed to analyze ear specimens, and immunohistochemical staining was conducted to detect IL-8 and MCP-1 in the scars. Compared with the control group, scar tissue in the experimental group was improved by color and texture. H&E-stained collagen fiber bundles were more organized after treatment as assessed by optical microscopy. The number of microvessels in the experimental group was decreased compared with that in the control group. Microvascular density was significantly reduced in the experimental group compared with the control group (27.16 ± 5.64 and 48.75 ± 8.25 mm2, respectively; P < 0.01). The mean optical densities of IL-8 and MCP-1 were significantly reduced in the experimental group compared with the control group (IL-8 0.016 ± 0.011 and 0.078 ± 0.023, respectively; MCP-1 0.018 ± 0.016 and 0.054 ± 0.038, respectively; both P < 0.01). The micro-plasma radio-frequency technique has a therapeutic effect on hypertrophic scars in rabbit ears.

Benefit of salvage total pharyngolaryngoesophagectomy for recurrent locally advanced head and neck cancer after radiotherapy.

BACKGROUND: The treatment modalities for recurrent locally advanced head and neck cancer failure after radiotherapy are limited with poor prognosis. Salvage supra-radical operation seems to be an option. It has not been established which patients will benefit from salvage total pharyngolaryngoesophagectomy. METHODS: We retrospectively reviewed 66 patients with previously irradiated recurrent T4 head and neck cancer who underwent salvage total pharyngolaryngoesophagectomy at our institution between January 2001 and June 2014. The clinical outcome and toxicities were analyzed. RESULTS: Flap loss occurred in 2 patients, and the incidence of fistulas and anastomosis strictures was 15.6% (10/66) and 13.6% (9/66), respectively. The median survival time of the entire cohort was 12 months. The interval between radiation and salvage surgery, and microscopic carotid artery invasion were identified as independent prognostic factors for overall survival. The 3-year overall survival rates of patients with (n = 33) and without (n = 33) risk factors were 9.1% and 47.2%, respectively (p = 0.007). A time interval between radiation and salvage surgery ≤6 months and previous concurrent chemotherapy or targeted therapy were risk factors for severe post-operative complications. CONCLUSIONS: Salvage total pharyngolaryngoesophagectomy is beneficial to selected patients with recurrent locally advanced head and neck cancer after radiotherapy.

Deep sequencing identifies deregulation of microRNAs involved with vincristine drug-resistance of colon cancer cells.

BACKGROUND: Vincristine (VCR) is a chemical that is widely used in tumor therapy. While long-term use can make tumor cells resistant to VCR, the underlying mechanisms of this resistance are still unclear. OBJECTIVE: This study aimed at investigating the role of microRNA (miRNA) in colon cancer drug resistance. METHODS: HCT-8 colon carcinoma cells were cultured and treated with different VCR concentrations to establish an HCT-8/VCR resistant cell line. Whole-genome screens, HiSeq 2500 sequencing, and bioinformatics methods were used to detect and analyze differences in miRNA expression between the drug-resistant HCT-8/VCR cells and non-resistant HCT-8 cells. Differential expression profiles of miRNAs were constructed based on sequencing result. RESULTS: The HCT-8/VCR resistant colon carcinoma cell line was established. With regard to the difference in drug resistance between HCT-8/VCR and HCT-8 cells, 24 miRNAs showed statistically significant differences in their expression (fold change > 4), of which 17 were up-regulated. Seven miRNAs were down-regulated. CONCLUSION: As abnormal expression of miRNAs was associated with VCR resistance of colon carcinoma cells, differences in miRNA expression may play a key role in VCR resistance of colon cancer cells.

Tissue degeneration 7 years after breast augmentation with injected polyacrylamide hydrogel (PAAG).

Injectable polyacrylamide hydrogel (PAAG) is a jelly-like transparent implant used in breast augmentations. This type of implant had been used since 1998, but its use was prohibited in China in 2006 due to numerous complications that had arisen from its use. In one case, a rare appearance of PAAG tissue degeneration was observed 7 years after an injectable breast augmentation using PAAG.

Down-regulation of TWIST decreases migration and invasion of laryngeal carcinoma Hep-2 cells by regulating the E-cadherin, N-cadherin expression.

PURPOSE: The transcription factor TWIST is an important factor in regulation of the epithelial-mesenchymal transition (EMT), which represents the primary stages during the metastasis of tumors. To identify the role of TWIST in the regulation of metastasis in laryngeal carcinoma Hep-2 cells, we investigated whether the alteration of TWIST has an effect on the Hep-2 cells morphology and whether the alteration of TWIST has an effect on the expression of E-cadherin, N-cadherin as well as the ability of cell motion, migration, and invasion. METHODS: Morphological changes of Hep-2 cells that were transfected a mircoRNA against TWIST vector were observed by the reserved microscope. Reverse transcription-polymerase chain reaction was performed in order to examine the mRNA expression of TWIST, E-cadherin, and N-cadherin. Western blotting was performed to examine the protein expression of TWIST, E-cadherin, and N-cadherin. Cell motion ability was examined by Scratch-wound assay. Transwell(™) chamber assays were used to determine cell migration and invasion. RESULTS: Transfecting a mircoRNA down-regulated TWIST expression at mRNA and protein levels. Down-regulation of TWIST expression induced morphological changes, such as the inversion of the EMT. Moreover, down-regulation of TWIST expression up-regulated E-cadherin and down-regulated N-cadherin expressions at mRNA and protein levels, respectively. Furthermore, we confirmed that down-regulation of TWIST expression decreased the motion, invasion, and migration ability of the Hep-2 cells. CONCLUSIONS: Down-regulation of TWIST expression decreases migration and invasion of laryngeal carcinoma Hep-2 cells by regulation of the E-cadherin, N-cadherin expression.

[Tubed pectoralis major myocutaneous flap for reconstruction of circumference pharyngoesophageal defects].

OBJECTIVE: To investigate the feasibility and efficacy of tubed pectoralis major myocutaneous flap in the reconstruction of circumferential defects following resection for locally advanced hypopharyngeal and cervical esophageal carcinoma. METHODS: From Dec. 2004 to Oct. 2008, 30 patients underwent immediate reconstruction by tubed pectoralis major myocutaneous flap for circumferential defects following resection of primary tumours. Among them, 22 were hypopharyngeal carcinoma, 7 were cervical esophageal carcinoma and one was recurrent laryngeal carcinoma involved the hypopharyngeal lumen. Five of 30 patients had received previous radiotherapy and three had failed in the previous surgical procedure. In this series, 12 patients had total pharyngolaryngectomy and 18 had total pharyngolaryngectomy and partial cervical esophagectomy. RESULTS: Postoperative pharyngocutaneous fistula formation occurred in 4 patients, 2 of them with previous radiotherapy and 2 with diabetes, and the fistulae healed later. Two patients developed anastomotic strictures at the upper junction, but they had good responses to dilatation treatment and had satisfactory oral intake. The postoperative follow-up time ranged from 8 to 56 months. Median follow-up was 18 months. One-year survival rate was 71.4% and three-year survival rate was 42.5%. CONCLUSIONS: The tubed pectoralis major myocutaneous flap is a reliable procedure to reconstruct hypopharyngeal circumferential defects following resection of advanced hypopharyngeal and cervical esophageal carcinoma. This method may be the optimal choice for the reconstruction of hypopharyngeal circumferential defects following resection of recurrent carcinoma. The incidence of fistula and stenosis could be kept at an acceptable level.

Alteration in TWIST expression: possible role in paclitaxel-induced apoptosis in human laryngeal carcinoma Hep-2 cell line.

AIM: To explore the relationship between alteration in the expression of TWIST, highly conserved transcription factor from the basic helix-loop-helix family, and apoptosis of Hep-2 cells induced by chemotherapeutic agent paclitaxel. METHODS: Morphological changes of Hep-2 cells were observed by acridine orange cytochemistry staining. Viability of Hep-2 cells treated with various concentrations of paclitaxel was examined by cell proliferation assay. Apoptosis was examined by flow cytometry. The mRNA and protein expression of TWIST in response to paclitaxel at 24 hours, 48 hours, and 72 hours was examined by reverse transcription-polymerase chain reaction (RT-PCR) and Western blotting, respectively. RESULTS: Typical morphological changes of apoptotic cells at 24 hours, 48 hours, or 72 hours after treatment wiyth paclitaxel (10x10(-9) mol/L) were observed. The cell survival rates significantly decreased in a concentration- and time-dependent manner (P=0.001). Paclitaxel-induced apoptosis increased with culture time (22.6+/-5.3% after 24 hours, 38.7+/-7.9% after 48 hours, and 52.4+/-14.3% after 72 hours; P=0.002). Both mRNA and protein expression of TWIST was markedly decreased at both mRNA levels and protein levels, at 24 hours, 48 hours, and 72 hours in the paclitaxel-induced apoptosis of Hep-2 cells (P<0.001). CONCLUSION: TWIST, which has a significantly decreased expression in response to paclitaxel in Hep-2 cells, may play a pivotal role in paclitaxel-induced apoptosis of Hep-2 cells.