A Novel KIF4A-Related Model for Predicting Immunotherapy Response and Prognosis in Kidney Renal Clear Cell Carcinoma.

BACKGROUND: The efficacy of chemotherapy in treating Kidney Renal Clear Cell Carcinoma (KIRC) is limited, whereas immunotherapy has shown some promising clinical outcomes. In this context, KIF4A is considered a potential therapeutic target for various cancers. Therefore, identifying the mechanism of KIF4A that can predict the prognosis and immunotherapy response of KIRC would be of significant importance. METHODS: Based on the TCGA Pan-Cancer dataset, the prognostic significance of the KIF4A expression across 33 cancer types was analyzed by univariate Cox algorithm. Furthermore, overlapping differentially expressed genes (DEGs1) between the KIF4A high- and lowexpression groups and DEGs2 between the KIRC and normal groups were also analyzed. Machine learning and Cox regression algorithms were performed to obtain biomarkers and construct a prognostic model. Finally, the role of KIF4A in KIRC was analyzed using quantitative real-time PCR, transwell assay, and EdU experiment. RESULTS: Our analysis revealed that KIF4A was significant for the prognosis of 13 cancer types. The highest correlation with KIF4A was found for KICH among the tumour mutation burden (TMB) indicators. Subsequently, a prognostic model developed with UBE2C, OTX1, PPP2R2C, and RFLNA was obtained and verified with the Renal Cell Cancer-EU/FR dataset. There was a positive correlation between risk score and immunotherapy. Furthermore, the experiment results indicated that KIF4A expression was considerably increased in the KIRC group. Besides, the proliferation, migration, and invasion abilities of KIRC tumor cells were significantly weakened after KIF4A was knocked out. CONCLUSION: We identified four KIF4A-related biomarkers that hold potential for prognostic assessment in KIRC. Specifically, early implementation of immunotherapy targeting these biomarkers may yield improved outcomes for patients with KIRC.

KIF4A Promotes Clear Cell Renal Cell Carcinoma (ccRCC) Proliferation in vitro and in vivo.

PURPOSE: To evaluate the expression in human clear cell renal cell carcinoma (ccRCC) tissues and explore the effects of kinesin family member 4A (KIF4A) on ccRCC progression. METHODS: GEPIA was used to evaluate the mRNA levels of KIF4A in human ccRCC tissues from TCGA database, and Immunohistochemistry (IHC) assays were performed to assess its expression in human ccRCC tissues collected in our hospital. The clinical-pathological analysis was performed to explore the correlation with KIF4A expression. The effects of KIF4A on ccRCC cell proliferation were detected through colony formation and MTT assays. Finally, the effects of KIF4A on tumor growth were measured using a mice model. RESULTS: Bioinformation results showed the expression of KIF4A mRNA was upregulated in ccRCC tissues and high expression of KIF4A was related with poor prognosis in ccRCC patients. We also found a high expression of KIF4A in human ccRCC tissues collected in our hospital. We also found its expression level was correlated with clinical characteristics, including T stage (P=0.035*) and lymphatic metastasis (P=0.028*). We further confirmed that knockdown of KIF4A suppressed cell proliferation in HTB-47 and CRL-1932 cells. Furthermore, KIF4A contributes to tumor growth of ccRCC cells in mice. CONCLUSION: We found the abnormal high expression of KIF4A in human ccRCC tissues and demonstrated that KIF4A could serve as a tumor induction gene.

miR-192 Is Overexpressed and Promotes Cell Proliferation in Prostate Cancer.

OBJECTIVE: Prostate cancer (PCa) is one of the most prevalent types of cancer among men worldwide. The incidence of PCa is increasing in China. Therefore, there is an urgent need to identify novel diagnostic and prognostic markers for PCa to improve the treatment of the disease. METHODS: The Cancer Genome Atlas (TCGA) and GEO database were used to analyze the expression of miR-192, and the relationship between miR-192 and the clinical features of patients with PCa. Cell cycle and cell proliferation assay were used to detect the functional roles of miR-192 in PCa. Bioinformatic analysis for miR-192-5p was performed using gene ontology and KEGG analysis. RESULTS: By analyzing the dataset of TCGA, we found that miR-192 was overexpressed in PCa samples compared to normal tissues and was upregulated in high-grade PCa compared to low-grade PCa. We also observed that higher miR-192 expression was associated with a shorter biochemical recurrence-free survival time. Our results also demonstrated that miR-192 promoted PCa cell proliferation and cell cycle progression. CONCLUSION: These results suggest that miR-192 may be considered for use as a potential diagnostic and therapeutic target of PCa.

Patchouli alcohol ameliorates dextran sodium sulfate-induced experimental colitis and suppresses tryptophan catabolism.

Despite the increased morbidity of ulcerative colitis (UC) in recent years, available treatments remain unsatisfactory. Pogostemon cablin has been widely applied to treat a variety of gastrointestinal disorders in clinic for centuries, in which patchouli alcohol (PA, C15H26O) has been identified as the major active component. This study attempted to determine the bioactivity of PA on dextran sulfate sodium (DSS)-induced mice colitis and clarify the mechanism of action. Acute colitis was induced in mice by 3% DSS for 7 days. The mice were then given PA (10, 20 and 40mg/kg) or sulfasalazine (SASP, 200mg/kg) as positive control via oral administration for 7 days. At the end of study, animals were sacrificed and samples were collected for pathological and other analysis. In addition, a metabolite profiling and a targeted metabolite analysis, based on the Ultra-Performance Liquid Chromatography coupled with mass spectrometry (UPLC-MS) approach, were performed to characterize the metabolic changes in plasma. The results revealed that PA significantly reduced the disease activity index (DAI) and ameliorated the colonic injury of DSS mice. The levels of colonic MPO and cytokines involving TNF-α, IFN-γ, IL-1ß, IL-6, IL-4 and IL-10 also declined. Furthermore, PA improved the intestinal epithelial barrier by enhancing the level of colonic expression of the tight junction (TJ) proteins, for instance ZO-1, ZO-2, claudin-1 and occludin, and by elevating the levels of mucin-1 and mucin-2 mRNA. The study also demonstrated that PA inhibited the DSS-induced cell death signaling by modulating the apoptosis related Bax and Bcl-2 proteins and down-regulating the necroptosis related RIP3 and MLKL proteins. By comparison, up-regulation of IDO-1 and TPH-1 protein expression in DSS group was suppressed by PA, which was in line with the declined levels of kynurenine (Kyn) and 5-hydroxytryptophan (5-HTP) in plasma. The therapeutic effect of PA was evidently reduced when Kyn was given to mice. In summary, the study successfully demonstrated that PA ameliorated DSS-induced mice acute colitis by suppressing inflammation, maintaining the integrity of intestinal epithelial barrier, inhibiting cell death signaling, and suppressing tryptophan catabolism. The results provided valuable information and guidance for using PA in treatment of UC.

The immune-regulating effect of Xiao'er Qixingcha in constipated mice induced by high-heat and high-protein diet.

BACKGROUND: Xiao'er Qixingcha (EXQ) has been extensively applied to relieve dyspepsia and constipation in children for hundreds of years in China. However, the therapeutic mechanism underlying its efficacy remained to be defined. The present study aimed to clarify the possible laxative and immune-regulating effects of EXQ on two models of experimental constipation in mice, which mimicked the pediatric constipation caused by high-heat and high-protein diet (HHPD). METHODS: The two models of constipated mice were induced by HHPD or HHPD + atropine respectively. To investigate the laxative and immune-regulating activities of EXQ, animals were treated with three doses of EXQ (0.75, 1.5 and 3 g/kg) for 7 consecutive days. The fecal output parameters (number and weight), weight of intestinal content and, the thymus and spleen indexes were measured. The levels of sIgA, IL-10, TNF-α and LPS in colon and serum were determined by ELISA. Furthermore, the pathological changes of colon tissue were examined after routine H&E staining. RESULTS: Both HHPD and HHPD + atropine treatments obviously inhibited the fecal output and reduced the colonic sIgA, prominently increased the levels of IL-10 and TNF-α in colonic tissue and elevated the contents of LPS in serum and colonic tissues. In contrast, oral administration of EXQ significantly improved the feces characters and dose-dependently decreased the intestinal changes in both models. In HHPD model test, EXQ efficaciously boosted the sIgA level in a dose-dependent manner, significantly elicited decreases in TNF-α and IL-10 levels, and evidently decreased the spleen and thymus indexes. In HHPD + atropine model test, EXQ treatment reversed the pathological changes by not only dramatically decreasing the spleen index and the levels of LPS and IL-10, but also markedly elevating the thymus index. Furthermore, microscopic observation revealed that EXQ treatment maintained the integrity of colonic mucosa, and protected the colonic tissues from inflammation in the both models. CONCLUSIONS: EXQ exhibited prominent laxative activity and effectively protected the colonic mucosal barrier in two models of constipated mice, of which the mechanism might be closely associated with its propulsive and immune-regulating properties. The current results not only validated the rationale for the clinical application of EXQ in pediatric constipation related symptoms, but also threw new light on the immune-inflammatory responses accompanied with chronic constipation pathology.

In silico analysis of the effect of mutation on epidermal growth factor receptor in non-small-cell lung carcinoma: from mutational analysis to drug designing.

Tyrosine kinase inhibitors (TKI)-resistant mutation in epidermal growth factor receptor's (EGFR) kinase domain is an important anomaly to look into. Studying the mutations at atomic level using molecular dynamics simulations gave us an insight into the architectural changes happening at the microscopic level. The knowledge was used to design new TKI whose function is devoid of the affect of the mutations in kinase domain. Traditional Chinese medicinal library was used for structure-based drug designing, where virtual screening was followed by ADME/Tox analysis and the shortlisted compounds were docked into the kinase domain of EGFR and simulated there using atomic-level selection of the grid. The shortlisted compounds from molecular docking analysis were subjected to MM-PBSA calculations. The in silico data generated is giving a strong lead compound for further in vitro and in vivo analysis.

Silencing of RTKN2 by siRNA suppresses proliferation, and induces G1 arrest and apoptosis in human bladder cancer cells.

Human bladder cancer is the most common urological malignancy in China. One of the causes of carcinogenesis in the cancer may be gene mutation. Therefore, the present study investigated the expression levels of Rhotekin 2 (RTKN2), a Rho effector protein, in human bladder cancer tissues and cell lines, and examined the effect of RTKN2 on the proliferation, cell cycle, apoptosis and invasion of human bladder cancer cell lines. The mRNA expression levels of RTKN2 in 30 human bladder cancer tissue samples were significantly higher, compared with those in 30 normal human bladder tissue samples. The protein expression levels of RTKN2 was markedly higher in T24 and 5637 cells, compared with those in four other human bladder cancer cell lines. The silencing of RTKN2 by small interfering (si)RNA inhibited cell proliferation and arrested cell cycle at the G1 phase, via reducing the expression levels of the MCM10, CDK2, CDC24A and CDC6 cell cycle­associated proteins in the T24 and 5637 cells. Furthermore, RTKN2 knockdown in the cells led to cell apoptosis and the suppression of invasion. These results suggested that RTKN2 is involved in the carcinogenesis and progression of human bladder cancer, indicating that RTKN2 may be a molecular target in cancer therapy.

Effects on Subtalar Joint Stress Distribution After Cannulated Screw Insertion at Different Positions and Directions.

We investigated the effects on subtalar joint stress distribution after cannulated screw insertion at different positions and directions. After establishing a 3-dimensional geometric model of a normal subtalar joint, we analyzed the most ideal cannulated screw insertion position and approach for subtalar joint stress distribution and compared the differences in loading stress, antirotary strength, and anti-inversion/eversion strength among lateral-medial antiparallel screw insertion, traditional screw insertion, and ideal cannulated screw insertion. The screw insertion approach allowing the most uniform subtalar joint loading stress distribution was lateral screw insertion near the border of the talar neck plus medial screw insertion close to the ankle joint. For stress distribution uniformity, antirotary strength, and anti-inversion/eversion strength, lateral-medial antiparallel screw insertion was superior to traditional double-screw insertion. Compared with ideal cannulated screw insertion, slightly poorer stress distribution uniformity and better antirotary strength and anti-inversion/eversion strength were observed for lateral-medial antiparallel screw insertion. Traditional single-screw insertion was better than double-screw insertion for stress distribution uniformity but worse for anti-rotary strength and anti-inversion/eversion strength. Lateral-medial antiparallel screw insertion was slightly worse for stress distribution uniformity than was ideal cannulated screw insertion but superior to traditional screw insertion. It was better than both ideal cannulated screw insertion and traditional screw insertion for anti-rotary strength and anti-inversion/eversion strength. Lateral-medial antiparallel screw insertion is an approach with simple localization, convenient operation, and good safety.

Clinicopathologic features of pleomorphic hyalinizing angiectatic tumor of soft parts.

BACKGROUND: Pleomorphic hyalinizing angiectatic tumor (PHAT) of soft parts is a rare soft tissue tumor, which is generally considered low-grade. To distinguish the tumor from other soft tissue lesions, we analyzed the clinicopathologic and ultrastructural features, immunophenotypes, and flow cytometric DNA ploidy of PHAT in 9 cases. METHODS: PHAT specimens were collected from 9 patients with PHAT from 1990 to 2004. Each specimen was cut into pieces and stained with hematoxylin-eosin, phosphotungstic acid-hematoxylin, Prussian blue, and Masson trichrome, respectively. Immunohistochemical stains for vimentin, S-100 protein, CD34, CD31, CD99, VEGF, desmin, CD117, alpha-SMA, and MIB-1 were performed with the Envision system. Flow cytometry was used in four specimens, two of which were observed by electron microscopy. RESULTS: In the 9 cases, the PHAT occurred at the lower extremity in 2 patients, inguinal in 2, waist in 1, forearm in 1, buttock in 1, foot in 1, and the chest wall in 1. All the lesions presented in the superficial subcutaneous tissues. Follow-up data were available in 7 of the patients, among whom 2 (28.6%) had recurrence after primary therapy. Microscopically, typical PHAT was characterized by sheet-like proliferation of spindle or pleomorphic cells and clusters of thin-walled hyalinized cstatic vessels. In some areas of the tumor, hemosiderin-laden spindle cells, numerous small single vessels, and myxoid extracellular matrix could be identified, indicating an "atypical PHAT". Mitotic figures were rare in all the cases. In 5 of the 9 patients (55.6%), the tumor was typical PHAT; and in the other 4 (44.4%), typical and atypical PHAT coexisted. Immunohistochemically, the neoplastic cells were positive for vimentin, CD34, CD99, and VEGF, but negative for S-100 protein, desmin, SMA, and CD31. In all the cases, the MIB-1 proliferative activity of the neoplastic cells was lower than 2%. Ultrastructural analysis did not reveal any evidence of specific differentiation. Aneuploidy was not detected by flow cytometry. CONCLUSIONS: Histologically, typical PHAT is characterized by spindle and pleomorphic cells associated with an angiectatic vasculature. The neoplastic cells often express vimentin and CD34, and may be positive for CD99 and VEGF. Ultrastructurally, the tumor usually has no specific differentiation. The low MIB-1 index and the absence of aneuploidy in PHAT indicate a non-malignancy. However, we consider the tumor as a borderline neoplasm because of its aggressive behaviour, and suggest wide local resection with tumor-free margin for the treatment of the disease.

Smad4 and ERK2 stimulated by transforming growth factor beta1 in rhabdomyosarcoma.

BACKGROUND: Transforming growth factor beta (TGF-beta) plays an essential role in the regulation of normal physiologic processes of cells. TGF-beta has been shown to regulate several mitogen-activated protein kinases (MAPK) pathways in several epithelial cells. However, the effects of TGF-beta on soft tissue sarcoma are seldom reported. Our previous studies suggested that there should be some other signal transduction pathways besides Smads, which are important to regulate the growth of human embryonal rhabdomyosarcoma (RMS) cells. In the present study, we examined the expression and functional relations of extracellular signal-regulated kinase 2 (ERK2) and Smad4 in human RMS tissue and a RMS cell line, RD. METHODS: RD cells and normal human primary skeletal myoblasts (Mb) were treated with TGF-beta1 to establish the expression profile of ERK2 at the mRNA and protein levels detected by RT-PCR and immunofluorescence. Immunohistochemistry was used to detect the expression of ERK2 and Smad4 in 50 tissue specimens of human RMS and 23 specimens of normal skeletal muscles. Follow-up of specimens was performed 6 months to 70 months later. RESULTS: RD cells and human RMS tissues showed the higher expression of ERK2 and Smad4 than the normal control, either the protein level or the mRNA level. And, exogenous TGF-beta1 stimulation can lead to higher expression of ERK2 and its nuclear translocation, so TGF-beta1 can also activated MAPK (ERK2) pathway, resulting in a sustained activation of ERK2 for at least 2 hours. Immunohistochemistry analysis, however, showed that there was no correlation between ERK2 and Smad4 protein. The overexpression of ERK2 and Smad4 had no indicative effects on histological subtypes, histological grading, gender, age, and prognosis. CONCLUSIONS: In RMS, signaling of TGF-beta1 from cell surface to nucleus can also be directed through the MAPK (ERK2) pathway besides the TGF-beta1/Smads pathway. The activation of ERK2 by TGF-beta1 may be Smad4 independent. Moreover, there may be some other tanglesome relationships between the TGF-beta1/Smads pathway and the MAPK pathway which takes part in the development, invasion and metastasis of tumor cells.

Myofibroblastic sarcoma of the nasal cavity and paranasal sinus: a clinicopathologic study of 6 cases and review of the literature.

OBJECTIVE: We describe the clinicopathologic features of 6 cases of myofibroblastic sarcoma (MS) occurring in the nasal cavity and paranasal sinus. STUDY DESIGN: The paraffin-embedded tissues of 6 cases of MS were stained immunohistochemically and examined by electron microscopy. RESULTS: Clinically, a painless enlarging mass was the most common symptom, followed by the nasal obstruction, epistaxis, copious rhinorrhea, and proptosis. Histologically, the tumors showed a diffusely infiltrative growth pattern and consisted mainly of spindle cells with abundant eosinophilic cytoplasm. The hypocellular myxoid areas and the hypercellular fibrous areas were identified. Immunohistochemically, all 6 tumors were positive for vimentin, alpha-smooth muscle actin, calponin, and fibronectin. Ultrastructural examination in 3 cases showed characteristic features of myofibroblast. Follow-up in 6 patients revealed high local recurrence rate (6 out of 6). CONCLUSION: Myofibroblastic sarcoma of the nasal cavity and paranasal sinus exhibit diverse histologic appearances and a strong aggressive behavior.

[Effects of transforming growth factor-beta/Smad signaling on the growth and apoptosis of human rhabdomyosarcoma cell line RD].

OBJECTIVE: To study the effects of TGF-beta/Smad signaling on the growth and apoptosis of human rhabdomyosarcoma cell line RD. METHODS: Biosynthesized short hairpin RNA (shRNA) was transfected into RD cells by cation liposome vector to suppress Smad4 expression. The mRNA and protein expression of Smad4 in RD after shRNA-transfection were examined by RT-PCR and Western blot respectively. Immunofluorescent staining was used to detect the location of Smad2/3 in RD by laser scanning confocal microscopy. The viability of RD cells was examined by MTT method and (3)H-thymidine incorporation assay. The apoptosis of RD was examined by flow cytometry analysis and fluorescent staining. RESULTS: The expression of mRNA and protein of Smad4 in RD were effectively suppressed by shRNA interference. Such suppression effectively interrupted the endogenous TGF-beta/Smad signaling and consequently blocked the translocation of Smad2/3. The interruption of endogenous TGF-beta/Smad signaling not only inhibited the growth of RD but also induced apoptosis of RD. Exogenous TGF-beta1 inhibited the growth of RD but did not influence the apoptosis of RD. CONCLUSION: shRNA interference can effectively interrupt the TGF-beta/Smad signaling by suppressing the expression of Smad4. TGF-beta/Smad signaling subtly regulates the growth and apoptosis of RD.

Clinicopathological, immunohistochemical, and ultrastructural study of 13 cases of melanotic schwannoma.

BACKGROUND: Melanotic schwannoma is a rare variant of schwannoma composed of melanin-producing cells with ultrastructural features of schwann cells. The description of the course of the tumors differs somewhat, but it is generally considered as a benign lesion. We investigated the clinicopathologic features, immunophenotypes, and ultrastructural features of 13 patients with nonpsammomatous melanotic schwannoma (NPMS). METHODS: Tumor specimens of each patient were sectioned and stained with hematoxylin-eosin, Fontana-Masson, Prussian blue, and periodic acid-Schiff (PAS). Immunohistochemical markers such as S-100, Leu-7, HMB-45, Melan-A, CK, EMA, vimentin, GFAP, laminin, collagen IV and MIB-1 were detected with the Envision immunohistochemical staining method. Four of the cases were observed by electron microscopy. RESULTS: Of the 13 patients, 8 were male and 5 female, aged from 11 to 92 years (mean, 38.6 years). The tumor sites included the spinal nerve root (5 patients), cranial nerve (1), greater omentum (1), subcutaneous tissue (3), mesentery (1), bone (1) and mediastinum (1). Eleven patients were followed up for over 2 years, with a mean of 5.9 years. One patient (9.1%) with a primary tumor in the greater omentum developed another primary tumor of the same type in the subcutaneous tissue of the abdominal wall after the first operation. Local recurrence of the tumor was seen in 2 patients (18.2%). One patient (9.1%) showed the local recurrence and metastasis. Seven patients (63.6%) showed no evidence of the recurrence or metastasis. Grossly, all tumors were well-circumscribed and the gross findings were suggestive of melanin-containing tumors. The tumor was composed of spindled and epithelioid cells with abundant intracytoplasmic melanin pigments. Nuclei were round and contained delicate, evenly distributed chromatins as well as small, distinct nucleoli. In some areas, the nucleoli were large and prominent. Rare mitoses were seen in most lesions except the larger omentum lesion. The pigment was shown to be positive for the Fontana-Masson and negative for Prussian blue and PAS. Immunohistochemical staining for S-100, Leu-7, HMB-45, Melan-A, and vimentin were strongly positive. Linear immunoreactions of both laminin and collagen IV was detected in all patients. Ultrastructurally, numerous elongated tumor-cell processes, duplicated basement membrane and melanosomes were observed in all developmental stages. CONCLUSIONS: Histologically, melanotic schwannoma is a rare variant of schwannoma composed of melanin-producing cells with ultrastructural features of schwann cells. Distinguishing between this tumor and malignant melanoma is of paramount importance in planning of management. Immunohistochemically, combined use of laminin and collagen IV is valuable in distinguishing melanotic schwannoma from malignant melanoma. Wide local resection and additional radiotherapy should be advocated. Further studies including cytogenetic or molecular biology are still required to better delineate melanotic schwannoma from malignant melanoma. Appropriate long-term follow-up is needed for all melanotic schwannomas.

Effects of transforming growth factor beta 1 on the growth of rhabdomyosarcoma cell line RD.

BACKGROUND: Transforming growth factor-beta (TGF-beta) can inhibit the growth of most epithelial and endothelial cells. The growth regulative role of TGF-beta on soft tissue sarcoma was seldom reported. Here we examined TGF-beta1 effects on the growth of human rhabdomyosarcoma cell RD and searched the relative molecular mechanism. METHODS: The viability of RD was examined by [(3)H]-thymidine incorporation and [3-(4,5-dimethylthiazol-z-yl)-2,5-diphenyl tetrazolium bromide] (MTT) assay. RD cell cycle was analysed by flow cytometry. The protein and mRNA of cell cycle regulative factors in RD were detected by Western blot and reverse transcription-polymerase chain reaction (RT-PCR), respectively. The kinase activity of cdk2 or cdk4 was examined by immunoprecipitation and kinase assay. Immunofluorescent staining was used to detect the location of cell cycle regulative factors in RD by laser scanning confocal microscope. RESULTS: TGF-beta1 inhibits RD proliferation by G1-arrest in cell cycle progression. TGF-beta1 can prominently up-regulate P27 of RD, then augment P27 to bind cyclinE-cdk2 complexes, which effectively suppress cdk2 kinase activity. P21 increased and c-myc decreased in RD due to TGF-beta1. Both P15 and cdk4 have not been involved in the growth inhibitory event. TGF-beta1 treatment induced P27 to congregate around nucleus. P21 pervaded from nucleus to both nucleus and cytoplasm by TGF-beta1 treatment. CONCLUSION: TGF-beta1 inhibits the proliferation of human rhabdomyosarcoma cell line RD and induces RD G1-arrest. This course is accomplished by TGF-beta1 up-regulating P27 to suppress cdk2 kinase activity. The induction of P21 and down-regulation of C-myc might participate in the growth-arrest event.

[Fragile histidine triad expression in rhabdomyosarcoma].

OBJECTIVE: To study the expression of fragile histidine triad (FHIT) protein in rhabdomyosarcoma(RMS) and the possible mechanisms of its effect on tumor. METHODS: Immunohistochemical technique(SP) was used to detect the expression of FHIT in 44 cases of RMS and 20 cases of normal skeletal muscles. RESULTS: Reduced expression of FHIT was 68.2% (30/44) in the cases of RMS, and was 35% (7/20) in the cases of normal skeletal muscles; a significant difference was seen between the two groups(P < 0.05). There was no significant relationship of the expression of FHIT with the sex of the patient and the histological type and grade of the tumor(P > 0.05). However, a significant relationship was observed between the expression of FHIT and the prognosis of the tumor in respect to relapse and metastasis of tumor(P < 0.05). CONCLUSION: The reduced expression of FHIT may play an important role in the development and progression of rhabdomyosarcoma, and thus may become a new prognostic marker in RMS.

[Study on microtubulin of human rhabdomyosarcoma].

OBJECTIVE: To detect the expression of microtubules in human rhabdomyosarcoma. METHODS: Expression of microtubulin-beta in 70 tissue slides from human rhabdomyosarcoma was detected by immunohistochemistry. Immunofluorescent staining was used to examine microtubules in PLA-802, A673 and RD under laser scanning confocal microscope. RESULTS: Expression of microtubulin-beta in human rhabdomyosarcoma tissue was widely decreased. The low expression rate of microtubulin-beta in histological grade-I tumor was 52.38%, and that in histological grade-III tumor 85% (P < 0.05). The low expression rate of microtubulin-beta in 32 cases with metastasis and recurrence was 87.5%, and that in 38 cases without metastasis and recurrence 55.26%. Microtubules in the three cell lines showed different degrees of maldevelopment. The most severe degree was observed in PLA-802, and the less severe degree in RD (P < 0.05). CONCLUSION: The microtubulin shows extensive low expression in human rhabdomyosarcoma. The decrease and hypogenesis of microtubules in human rhabdomyosarcoma have relationship with tumor's histological grade, malignant degree, metastasis, and recurrence.

[Regulation of growth inhibition by transforming growth factor beta1 in rhabdomyosarcoma RD cell line].

OBJECTIVE: To study the regulatory effect of TGF-beta1 on growth of rhabdomyosarcoma RD cell line. METHODS: After various durations of TGF-beta1 treatment, the viability of RD cell line was examined by growth rate measurement, MTT assay and (3)H-thymidine incorporation. The cell cycle was analyzed by flow cytometry. Immunofluorescent staining was used to localize p15, p21 and p27 in RD cell line under laser scanning confocal microscope. The protein and mRNA of p15, p21 and p27 in RD cell line were detected by western blot and reverse transcriptase-polymerase chain reaction respectively. RESULTS: The viability of RD cell line treated with TGF-beta1 was obviously decreased. RD cell line was arrested in G(1) phase by TGF-beta1. There was increased expression of p21 and p27 in RD cell line with TGF-beta1 treatment at protein and mRNA levels. The expression of p21 in RD cell line was seen in both nucleus and cytoplasm after 24 hours of TGF-beta1 treatment. The expression of p15 showed no obvious changes upon TGF-beta1 treatment. CONCLUSIONS: TGF-beta1 inhibits growth of RD cell line and induces G(1)-arrest. It up-regulates protein and mRNA of p21 and p27 and shows no obvious influence on p15 expression. The growth arrest of RD cell line may result from the up-regulation of p21 and p27 by TGF-beta1.

Systematic analysis of the TGF-beta/Smad signalling pathway in the rhabdomyosarcoma cell line RD.

Transforming growth factor-beta (TGF-beta) is a multifunctional regulator of cell growth and differentiation, whose actions are highly cell type specific. To study the role of the TGF-beta1 autocrine loop in regulating growth and myogenic differentiation in the human rhabdomyosarcoma cell line, RD, an attempt was made to establish a framework for the expression of several components of TGF-beta1/Smad signalling pathway at the mRNA and protein levels by reverse transcription-polymerase chain reaction (RT-PCR) and Western blot analysis in RD cells compared with the normal myoblasts. Higher exogenous concentration of TGF-beta1 was necessary to reach a growth-inhibition effect, whereas TGF-beta1 downregulated the expression of myosin heavy-chain mRNA at lower concentrations than that was required for growth inhibition. Treatment with TGF-beta1 significantly decreased the number of sarcomeric actin and myosin-expressing cells. In this study, we have shown that RD cells displayed higher expression of TbetaRI, TbetaRII, Smad2 and Smad4 at both the mRNA and protein levels than myoblasts. Smad3 and Smad7 mRNA were expressed at higher level in RD cells than in myoblasts. The staining patterns of TbetaR and Smads suggest that they may transduce different TGF-beta1 signalling in RD cells than in myoblasts. TGF-beta1 signalling induced a rapid relocation of Smad2 to the nucleus; in contrast, Smad4 remained localized to the cytoplasm unless it was coexpressed with Smad2. These studies suggest that signalling from the cell surface to the nucleus through Smad proteins is a required component of TGF-beta1-induced cell response in RD cells. The RD cell line is a suitable model to study the TGF-beta autocrine loop involved in growth and differentiation of RMS.

[Specific loss of heterozygosity of chromosome 3p loci in soft tissue leiomyosarcoma].

OBJECTIVE: To analyze the loss of heterozygosity (LOH) at 5 loci on chromosome 3p in soft tissue leiomyosarcoma (LMS). METHODS: LOH was detected in 22 cases of LMS using PCR-silver staining targeting 5 microsatellite sites on 3p14.2-pter. Relation between LOH and LMS clinical pathological features was also analyzed. RESULTS: Ten of 22 LMS samples showed LOH at more than one locus (45.4%). Among the 5 loci, LOH occurred more frequently at D3s1295 (36.8%) and D3s1289 (10.5%), but absent at D3s1293. No significant difference was found on LOH incidence between different grade, size and location of LMS. CONCLUSIONS: LOH on chromosome 3p14.2-23 region is relatively frequent in LMS. Region around D3s1295 and D3s1289 may harbor tumor suppressor gene relating to LMS.