| The cells receive the stimulation from the extracellular signals via the receptors located on the cellular membrane as well as the ones within the cells. After a series of complicated signal transformation procession, these signals begin to influence the biological functions of cells. The enzymes in charge of modulating the protein phosphorylation is classified into two main categories: the first group is the Protein Kinases (PKs), the second group is the Protein phosphotases (PPs). However, the Protein Tyrosine Phosphatases (PTPs) is another kind of enzyme deprived of metal ligand which initiates the catalysis process by virtue of a covalent intermedium of phosphorylated half-cystineThe TC-PTP, a member of the protein tyrosine phosphotase family, is derived from the monoclonal products of the cDNA library of the human peripheral blood. Due to the differences in their shearing patterns, there are two main kinds of TC-PTP whose only variance lies in their different carboxyl ends. One kind of TC-PTP, whose molecular mass is 45KD, is mainly distributed within the nucleus of the cells; the other one with a molecular mass of 48KD is located in the endocytoplasmic reticulum. The expression of the two types of TC-PTP is commonly discovered within the human bodies; however, only the 45KDa TC-PTP is found to be expressed in mice. The TC-PTP is a intracellular protein tyrosine phosphotase whose carboxyl end is linked to nuclear localization signal(NLS). The chief active site of TC-PTP is the catalysis structural domain which is mainly located within the nucleus of the cells of mammals.The highly expression of TC-PCP, which engages in the cellular signal transmission of the immune system, is common in the embryonic cells, mature cells as well as the hematopoietic tissues. Recent studies confirm that as a regulatory factor for the signal transduction pathway of growth factor receptors, the TC-PTP plays a crucial role in the signal transduction pathways of insulin and JAK-STAT. The important correlation between TC-PTP and the medullization of mammals is also proved to be valid by the establishment of animal models.The role of TC-PTP in tumorigenesis is now gaining prevalence among humans. The overexpression of TC-PTP lack of nucleic localization can alter the phenotype of Rat2 cells. As a result, the steady expression of v-fms in cells would inhibit the potential of cells in seducing the tumorigenesis. Delta EGFR, a shearing patterns of epidermal growth factor receptor (EGFR) expressed in malignant spongiocytoma, is a kind of special substrates for TC-PTP. Furthermore, The excessive expression of TC-PCP in malignant spongiocytoma inhibited the cell multiplication and tumorigenesis in extracorporeal experimentation.Both JAK and STATS are playing a pivotal role in regulating the growth and differentiation of tumor cells. Inappropriate activation of STATS has been found in many entities as well as hematological malignant tumors, especially in leukemia. The phosphorylation of the residues of tyrosine and serine in STAT1.3.5 has been witnessed in acute and chronic leukemia. Interestingly, these molecules have already been acknowledged as the substrates for TC-PTP. In this sense, the low-expression of TC-PTP could be discovered in these pathological phenomena. The reduction of the expression of TC-PTP is deemed to be related with the activation of STATS.Based upon these discoveries, it is likely that TC-PTP is playing a negative role in tumorigenesis. Further study insofar as the expression of TC-PTP in human tumor cells would serve to facilitate the illumination and definition of the role of TC-PTP in tumorigenesis.Lung cancer is one of the most popular malignant tumors which intimidate human health. In most cases, lung cancer derives from the epithelium of bronchi. For this reason, it has another name-bronchiogenic carcinoma. According to clinical practices, lung cancer is classified into two types: small cell lung caner (SCLC) and nonsmall-cell lung cancer(NSCLC). The NSCLC, which constitutes 75-80% of the total cases of lung cancer, is generally discovered at the advanced stage which renders it insensitive to neither radiotherapy nor chemical therapy. Accordingly, it is very difficult to develop an effective therapy for this kind of disease.Breast cancer has been the major culprit for claiming the lives of numerous women. Every year 1.2 million women fall victim to breast cancer and 500 thousands of them finally succumb to this deadly disease. Breast cancer, whose biological behavior is influenced by estrogen and progestogen at large, is one kind of hormone dependent tumor. Clinical analysis of estrogen receptor (ER) and progestogen receptor (PR) level is of great importance in the selection of endocrine therapy, the formulation of combined therapy as well as the anticipation of prognosis for breast cancer. The onset of breast cancer is related with many factors, such as the epithelium growth factor receptor(EGFR) which serves as an important regulatory factor the growth of normal mammary gland epithelium. It has been confirmed the existence of EGFR in the tissue most normal mammary gland as well as 30%-40% of breast cancer. Besides, EGFR is the key point in the proliferation of tumor cells. Furthermore, the overexpression of EGFR is related with the negative prognosis of this disease.In some researches involving the application of siRNA to interfere the expression of STAT3 in the cell strain of Lewis lung cancer, scientists examined the inhibition of STAT3 expression and the induction for apoptosis of Lewis lung cancer cell strain on the level of mRNA and protein. At the same time, other documents indicate that the inhibition of JAK could obstruct the synergistic action of IFN-γin the apoptosis process induced by Fas of the NSCLC A549 cell strain. Considering the fact that JAK family, STAT family as well as the EGFR could serve as the substrate for TC-PTP, it is reasonable for us to explore the unknown effect of TC-PTP during the onset and proliferation of lung cancer and breast cancer.In this experiment, after we amplify the catalytic structural domain of TC-PTP according to the template of the cDNA of TC-PTP via PCR (Polymerase chain reaction), the product-?TC-PTP, is then ligated with the expression vector of pT7. As we seduce the proliferation of the E.coli Rosetta(DE3)with pT7 plasmid, the soluble ?TC-PTP protein is purified via ion exchange chromatography and gel chromatography respectively. Activity analysis confirms the PTPs activity of the product.We establish the expression vector for the catalytic site of TC-PTP and accomplish the soluble expression of it successfully. After the analysis of activity and the kinetic analysis of enzyme reaction, we confirm that ?TC-PTP can be used as the marker for selecting the inhibitor of TC-PTP for high catalytic activity of ?TC-PTP and serve as the premise for further research on therapy for diseases concerning TC-PTP.Subsequently, we immunize the rabbits with the purified ?TC-PTP protein and purify the obtained post-immunization serum with the antigen-coating PVDF membrane, and consequently, we acquire the polyclonal antibody of ?TC-PTP. We examine the valence and sensitivity of the polyclonal antibody of ?TC-PTP and come to the conclusion that it can identify TC-PTP specificly and therefore can be utilized for studying the function of TC-PTPIn this study we have successfully obtained and purified the highly-sensitive and polyvalent polyclonal antibody of ?TC-PTP. As TC-PCP is playing a important role in many signal transduction pathways, the research for the biological function of TC-PTP has become the hotspot. For this matter, the preparation of polyclonal antibody of TC-PTP would serve as prompting impetus for further study of the biological function of TC-PTP.Then we conduct a series of immunohistochemical analyses on tissue samples of NSCLC and mammary infiltrate duct cancer as well as their comparative groups; we also analyze the correlation between the expression of TC-PTP, ER and PR at the same timeAccording to the results of our study, the expression of TC-PTP is detected in normal lung tissues. The expression level of TC-PTP in pulmonary squamous cell carcinoma is higher than that in normal lung tissue. However, there is no significant difference in the expression level of TC-PTP between pulmonary adenocarcinoma and normal lung tissue. Thus, we come to the conclusion that TC-PTP serves as a positive regulator in the process of onset and development of pulmonary squamous cell carcinoma and its accurate role in the proliferation of pulmonary adenocarcinoma is still inaccurate. The comparative high-level expression of TC-PTP in mammary infiltrate duct cancer than normal mammary tissue indicates TC-PTP serves as a positive regulator in the proliferation of mammary carcinoma cells. For that matter, we witness an obvious discrepancy between recent studies and bygone studies. In this sense, more study and evidence are needed to illuminate the unknown function of TC-PTP in the development of non-small cell lung cancer (NSCLC) and mammary infiltrate duct cancer as well as cellular signal transduction pathways.The expression level of TC-PTP differs significantly from that of PR rather than ER in mammary infiltrate duct cancer. Accordingly, the study on TC-PTP may help us to predicate the prognosis of patients. Moreover, the expression of TC-PTP could indicate the situation of PR, and vice versa. To understand the complicated mechanism of the network regulating system involving TC-PTP, ER and PR, further study are imperative.In sum, we successfully established a series of test system concerning the study of the biological function of TC-PTP: we constructed the expression vector for the catalytic domain of TC-PTP and accomplished its soluble expression. The template of ?TC-PTP of high catalytic activity, we created the polyclonal antibody of ?TC-PTP, the latter serves as effective means to study the biological function of TC-PTP. The advent of this system is of great importance in the study of the biological function of TC-PTP and thus provide strong premise for further study concerning the relationship between TC-PTP and human diseases. In one word, this system serves as the guideline for the diagnosis, prognosis and reasonable therapy for the TC-PTP-related diseases. At the same time, this system provide a effective research method for the study of other protein phosphatases, and serves as the reference and directions for the relationship between PTPs and human diseases.
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