miR-374b-5p suppresses RECK expression and promotes gastric cancer cell invasion and metastasis

AIM: To profile expression of microRNAs (miRNAs) in gastric cancer cells and investigate the effect of miR-374b-5p on gastric cancer cell invasion and metastasis.

Tumor microenvironment: driving forces and potential therapeutic targets for breast cancer metastasis

Distant metastasis to specific target organs is responsible for over 90%of breast cancer?related deaths,but the underlying molecular mechanism is unclear.Mounting evidence suggests that the interplay between breast cancer cells and the target organ microenvironment is the key determinant of organ?specific metastasis of this lethal disease.Here,we highlight new findings and concepts concerning the emerging role of the tumor microenvironment in breast cancer metastasis;we also discuss potential therapeutic intervention strategies aimed at targeting compo?nents of the tumor microenvironment.

Regarding on the Fractional Mathematical Model of Tumour Invasion and Metastasis

In this paper,we analyze the behaviour of solution for the system exemplifying model of tumour invasion and metastasis by the help of q-homotopy analysis transform method(q-HATM)with the fractional operator.The analyzed model consists of a system of three nonlinear differential equations elucidating the activation and the migratory response of the degradation of the matrix,tumour cells and production of degradative enzymes by the tumour cells.The considered method is graceful amalgamations of q-homotopy analysis technique with Laplace transform(LT),and Caputo–Fabrizio(CF)fractional operator is hired in the present study.By using the fixed point theory,existence and uniqueness are demonstrated.To validate and present the effectiveness of the considered algorithm,we analyzed the considered system in terms of fractional order with time and space.The error analysis of the considered scheme is illustrated.The variations with small change time with respect to achieved results are effectively captured in plots.The obtained results confirm that the considered method is very efficient and highly methodical to analyze the behaviors of the system of fractional order differential equations.

Study on the mechanism of tRNA-ValAAC-5 in promoting the proliferation and migration of hepatocellular carcinoma cells

Objective:To demonstrate the role and mechanism of tRNA-ValAAC-5 expression in hepatocellular carcinoma(HCC)cells.Methods:The expression levels of tRNA-ValAAC-5 in HCC(Hep3B,HuH7,SNU398,Hep3G2)and human hepatocellular carcinoma(THLE2,THLE3)were detected by real-time PCR.HEP3B and Hep3G2 cells were respectively transfected with tRNA-ValAAC-5-inhibitor and tRNA-ValAAC-5-NC as the inhibitor group and the NC group.Then the ability of cell proliferation was detected by CCK-8 assay and the ability of invasion and metastasis was detected by Transwell assay.The protein expression levels of p21,Matrix metalloproteinase 2(MMP2)and Matrix metalloproteinase 9(MMP9)were determined by Western blot.Results:The relative expression of tRNA-ValAAC-5 in Hep3B,HuH7,SNU398 and Hep3G2 cells were significantly higher than THLE2 and THLE3 cells,the differences were statistically significant(P<0.05).After tRNA-ValAAC-5-inhibitor transfection,the expression of tRNA-ValAAC-5 in Hep3B and Hep3G2 cells were reduced than tRNA-ValAAC-NC group.Both of the differences were statistically significant(t=36.52,27.45,P<0.001),which indicated the transfection was successful.The proliferative ability of Hep3B and Hep3G2 cells transfected with tRNA-ValAAC-5-inhibitor after 24,48,72,96 h were inhibited effectively compared with tRNA-ValAAC-5-NC group.All of the differences were statistically significant in Hep3B(t=5.25,8.23,7.33,14.16,P<0.001)and Hep3G2(t=4.25,5.11,9.39,7.59,P<0.001)cells.The number of invasion and metastasis of Hep3B and Hep3G2 cells were reduced in tRNA-ValAAC-5-inhibitor group compared with tRNA-ValAAC-5-NC group,there was significant difference(t=14.01,21.85,P<0.001).The protein expression levels of P21 were lower,MMP2 and MMP9 were higher in tRNA-ValAAC-5-inhibitor group compared with tRNA-ValAAC-5-NC group,the differences were statistically significant in Hep3B(t=8.96,12.80,4.652,P<0.001)cells and Hep3G2(t=15.17,22.36,12.61,P<0.001)cells.Conclusion:tRNA-ValAAC-5 can effectively promote the proliferation,invasion and metastasis of HCC,and its possible mechanism is related to regulating the expression of p21,MMP2 and MMP9.

Blockade of the deubiquitinating enzyme USP48 degrades oncogenic HMGA2 and inhibits colorectal cancer invasion and metastasis

HMGA2,a pivotal transcription factor,functions as a versatile regulator implicated in the progression of diverse aggressive malignancies.In this study,mass spectrometry was employed to identify ubiquitin-specific proteases that potentially interact with HMGA2,and USP48 was identified as a deubiquitinating enzyme of HMGA2.The enforced expression of USP48 significantly increased HMGA2 protein levels by inhibiting its degradation,while the deprivation of USP48 promoted HMGA2 degradation,thereby suppressing tumor invasion and metastasis.We discovered that USP48 undergoes SUMOylation at lysine 258,which enhances its binding affinity to HMGA2.Through subsequent phenotypic screening of small molecules,we identified DUB-IN-2 as a remarkably potent pharmacological inhibitor of USP48.Interestingly,the small-molecule inhibitor targeting USP48 induces destabilization of HMGA2.Clinically,upregulation of USP48 or HMGA2 in cancerous tissues is indicative of poor prognosis for patients with colorectal cancer(CRC).Collectively,our study not only elucidates the regulatory mechanism of DUBs involved in HMGA2 stability and validates USP48 as a potential therapeutic target for CRC,but also identifies DUB-IN-2 as a potent inhibitor of USP48 and a promising candidate for CRC treatment.

Role of adhesion molecules in cancer and targeted therapy

Adhesion molecules mediate cell-to-cell and cell-to-extracellular matrix interactions and transmit mechanical and chemical signals among them.Various mechanisms deregulate adhesion molecules in cancer,enabling tumor cells to proliferate without restraint,invade through tissue boundaries,escape from immune surveillance,and survive in the tumor microenvironment.Recent studies have revealed that adhesion molecules also drive angiogenesis,reshape metabolism,and are involved in stem cell self-renewal.In this review,we summarize the functions and mechanisms of adhesion molecules in cancer and the tumor microenvironment,as well as the therapeutic strategies targeting adhesion molecules.These studies have implications for furthering our understanding of adhesion molecules in cancer and providing a paradigm for exploring novel therapeutic approaches.

Reduced expression of P120 catenin in cholangiocarcinoma correlated with tumor clinicopathologic parameters

AIM： To investigate the relationship between the expression of P120 and the clinicopathologic parameters in intrahepatic cholangiocarcinoma （ICC）. METHODS： An immunohistochemical study of E-cadherin and P120 catenin was performed on 42 specimens of ICC with a Dako Envision kit. RESULTS： The expression of E-cadherin and P120 was reduced in 27 cases （64.3%） and 31 cases （73.8%）, respectively. Both E-cadherin and P120 expressions were significantly correlated with the tumor histological grade （χ^2 = 9.333, P = 009 and χ^= 11.71, P = 0.003）, TNM stage （χ^= 8.627, P = 0.035 and χ^= 13.123, P = 0.004）, intrahepatic metastasis （χ^= 7.292, P = 0.007 and χ^= 4.657, P = 0.041, respectively） and patients′ survival （χ^= 6.351, P = 0.002 and χ^= 4.023, P = 0.000, respectively）. In addition, the expression of P120 was in concordance with that of E-cadherin （χ^ = 13.797, P = 0.000）, indicating that the expression of P120 may be dependent on that of E-cadherin. Finally, only P120 expression was found to be an independent prognostic factor in Cox regression model （r = 0.088, P = 0.049）. CONCLUSION： Down-regulated expression of E-cadherin and P120 occurs frequently in ICC and contributes to the progression and development of tumor. Both of them may be valuable biologic markers for predicting tumor invasion, metastasis and patients′ survival, but only P120 is an independent prognostic factor for ICC.

Association of E-cadherin and β-catenin with metastasis in nasopharyngeal carcinoma

Background This study was designed to detect methylation of E-cadherin gene promoter and gene mutation of β-catenin in exon 3 and their expression of protein and mRNA in primary tumor and lymph node metastatic tumor of nasopharyngeal carcinoma (NPC), and investigate the mechanism of invasion and metastasis of neoplastic cells in NPC Methods Fourty-two fresh biopsy samples were taken from untreated NPC patients at the Affiliated Hospital of Sun Yat-sen Medical College, Sun Yat-sen University, Guangzhou, China during the period of 1999-2002 Among them 21 were taken from primary tumors and the other 21 from lymph node metastatic tumors The gene promoter methylation of E-cadherin was detected by methylation-specific PCR (MSP) The mutation in exon 3 of β-catenin was detected by direct sequencing analysis RT-PCR, Western blot and immunohistochemical staining were used to detect the mRNA and protein expression patterns in both primary and metastatic tumors of NPC Results Down-regulated expression of E-cadherin in metastatic tumor was compared with that in primary tumor Reduced expression of E-cadherin was found to be correlated with lymph node metastatic tumor of NPC ( P =0 004); but there was no obvious correlation between primary and metastatic tumors in the expression of β-catenin ( P =0 698) The mRNA expression level of E-cadherin in metastatic tumors decreased significantly compared with that in primary tumors However, little change was observed in the mRNA level of β-catenin in different tumor tissues Only 4 samples (19 1%) displayed gene promoter methylation of E-cadherin in primary tumor and 10 samples (47 6%) showed methylated form of E-cadherin The gene promoter methylation of E-cadherin was more common in metastatic tumor than in primary tumor of NPC ( P =0 024) Only 2 (4 76%) of the 42 samples showed mutations in exon 3 of β-catenin at 41 (T41A, ACCGCC) and codon 47 (S47T, AGTACT) The cytoplasmic and nuclear expression of β-catenin in tumor was not found in any samples of NPC Conclusions The results suggest that the downregulation of E-cadherin results from the gene promoter aberrant methylation of E-cadherin and that the methylation of E-cadherin plays an important role in invasion and metastasis of tumor cells in NPC However, β-catenin mutation is an infrequent event in NPC, and β-catenin is not a critical factor influencing the invasion and metastasis of tumor cells in NPC

Role of tissue factor in hepatocellular carcinoma genesis, invasion and metastasis

Background Numerous studies indicate that tissue factor （TF）, namely tissue thromboplastin, has a close relationship with malignant tumor genesis and progress. It contributes to blood coagulation as well as the regulation of cellular differentiation, the formation of blood vessels, and also tumor recurrence and metastasis. The present study aimed to detect TF expression in hepatocellular carcinoma （HCC） patients and to elucidate its association with prognosis and clinical features of the disease. Methods The plasma TF levels of 50 HCC patients and 30 controls were assayed by ELISA. The expressions of TF mRNA and protein in HCC tissues, adjacent tissues and normal tissues were detected by reverse transcription- polymerase chain reaction （RT-PCR） and Western blotting. The acquired data were analyzed with related clinic-pathological documents. The patients were followed up for five years, and the relationship between TF and prognosis was analyzed. Results The plasma TF levels were significantly increased in HCC compared to the controls （P 〈0.05）, presenting a close relationship with differentiation level, tumor size and hepatocirrhosis occurrence （P 〈0.05）. There were remarkably higher values in cases of lymphatic metastasis, extrahepatic metastasis and portal tumor thrombus （PTT） （P 〈0.05） compared to non-metastasis or non-tumor thrombus, but no significant difference with different focus number or envelope （P 〉0.05）. The positive rates and the relative expression of TF mRNA in HCC tissue were 63.0% （17/27） and 0.567±0.268, respectively, significantly higher than that in adjacent tissues or normal tissues （P 〈0.05）. In the patients with positive results, the relative expression intensity varied significantly with different tumor size and index of local invasion and metastasis （P 〈0.05）. The positive rates and the relative expression intensities of TF protein in HCC tissue were 74.1% （20/27） and 4.093±1.256, respectively, significantly higher than those in adjacent tissue or normal tissue （P 〈0.05）. In the patients with positive results, the relative expression intensity showed significant difference in different tumor size, differentiation level, and index of local invasion and metastasis （P 〈0.05）. Conclusions The TF levels were significantly higher in plasma and tissues of HCC patients, presenting a close relationship with the index of invasion and metastasis. It indicated that TF might be related to differentiation and metastasis of HCC.

Adverse effects of chemoradiotherapy on invasion and metastasis of tumor cells

The phenomenon of enhanced invasion and metastasis of residual tumor cells has been observed in an increasing number of patients receiving chemoradiotherapy recently,and tumor metastasis will undoubtedly limit patient prognosis.However,the key mechanism by which chemoradiotherapy affects the invasion and metastasis of tumor cells remains unclear.Studies have shown that chemoradiotherapy may directly act on tumor cells and alter the tumor microenvironment,or induce cell apoptosis and autophagy to promote tumor cell survival and metastasis.In this review,we summarize the potential mechanisms by which chemoradiotherapy may affect the biological behavior of tumor cells and open up new avenues for reducing tumor recurrence and metastasis after treatment.These insights will improve the efficacy of chemoradiotherapy.