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Full-Text Articles in Medicine and Health Sciences
Deregulation Of Muc4 In Gastric Adenocarcinoma: Potential Pathobiological Implication In Poorly Differentiated Non-Signet Ring Cell Type Gastric Cancer., S. Senapati, P. Chaturvedi, P. Sharma, G Venkatraman, Jane L. Meza, W. El-Rifai, H. K. Roy, Surinder K. Batra
Deregulation Of Muc4 In Gastric Adenocarcinoma: Potential Pathobiological Implication In Poorly Differentiated Non-Signet Ring Cell Type Gastric Cancer., S. Senapati, P. Chaturvedi, P. Sharma, G Venkatraman, Jane L. Meza, W. El-Rifai, H. K. Roy, Surinder K. Batra
Journal Articles: Biochemistry & Molecular Biology
MUC4 is a large, heavily glycosylated transmembrane mucin, that is implicated in the pathogenesis of various types of cancers. To date, no extensive study has been done to check the expression and functional significance of MUC4 in different types of gastric adenocarcinomas. Here, we report the expression profile of MUC4 in gastric adenocarcinomas and its function in poorly differentiated gastric non-signet ring cell carcinoma (non-SRCC) type cells. Immunohistochemical analysis using tissue microarray (TMA) showed a significant difference in MUC4 expression between normal adjacent (n = 45) and gastric adenocarcinoma (n = 83; P < 0.001). MUC4 expression was not associated with tumour type, stage or with the degree of differentiation. To gain further insight into the significance of MUC4 expression in gastric non-SRCC cells, MUC4 was ectopically expressed in AGS, a poorly differentiated gastric non-signet ring cell line. The MUC4 overexpressing cells (AGS-MUC4) showed a significant increase (P < 0.005) in cell motility and a decrease in cellular aggregation as compared with the vector-transfected cells. Furthermore, in vivo tumorigenicity analysis revealed that animals transplanted with the MUC4 overexpressing cells (AGS-MUC4) had a greater incidence of tumours (83%) in comparison to empty vector control (17%). In addition, the expression of MUC4 resulted in enhanced expression of total cellular ErbB2 and phosphorylated ErbB2. In conclusion, our results showed that MUC4 is overexpressed in gastric adenocarcinoma tissues, and that it has a role in promoting aggressive properties in poorly differentiated gastric non-SRCC cells through the activation of the ErbB2 oncoprotein.
Mitochondrial Redox Signaling By P66shc Is Involved In Regulating Androgenic Growth Stimulation Of Human Prostate Cancer Cells., Suresh Veeramani, Ta-Chun Yuan, Fen-Fen Lin, Ming-Fong Lin
Mitochondrial Redox Signaling By P66shc Is Involved In Regulating Androgenic Growth Stimulation Of Human Prostate Cancer Cells., Suresh Veeramani, Ta-Chun Yuan, Fen-Fen Lin, Ming-Fong Lin
Journal Articles: Biochemistry & Molecular Biology
p66Shc is shown to negatively regulate the life span in mice through reactive oxygen species (ROS) production. Recent reports, however, revealed that p66Shc protein level is significantly elevated in several human cancer tissues and growth-stimulated carcinoma cells, suggesting a mitogenic and carcinogenic role for p66Shc. In this communication, we demonstrate for the first time that p66Shc mediates androgenic growth signals in androgen-sensitive human prostate cancer cells through mitochondrial ROS production. Growth stimulation of prostate cancer cells with 5alpha-dihydrotestosterone (DHT) is accompanied by increased p66Shc level and ROS production, which is abolished by antioxidant treatments. However, antioxidant treatments do not affect …
Muc4 Activates Her2 Signalling And Enhances The Motility Of Human Ovarian Cancer Cells., Moorthy P. Ponnusamy, A. P. Singh, Maneesh Jain, S. Chakraborty, N. Moniaux, Surinder K. Batra
Muc4 Activates Her2 Signalling And Enhances The Motility Of Human Ovarian Cancer Cells., Moorthy P. Ponnusamy, A. P. Singh, Maneesh Jain, S. Chakraborty, N. Moniaux, Surinder K. Batra
Journal Articles: Biochemistry & Molecular Biology
The mucin MUC4 is a high molecular weight transmembrane glycoprotein. It consists of a mucin-type subunit (MUC4alpha) and a transmembrane growth factor-like subunit (MUC4beta). The mucin MUC4 is overexpressed in many epithelial malignancies including ovarian cancer, suggesting a possible role in the pathogenesis of these cancers. In this study, we investigated the functional role of MUC4 in the human ovarian cancer cell line SKOV3. The mucin MUC4 was ectopically expressed by stable transfection, and its expression was examined by western blot and confocal microscopy analyses. The in vitro studies demonstrated an enhanced motility of MUC4-expressing SKOV3 cells compared with the …
Muc4 And Muc5ac Are Highly Specific Tumour-Associated Mucins In Biliary Tract Cancer., W. R. Matull, F. Andreola, A. Loh, Z. Adiguzel, M. Deheragoda, U. Qureshi, Surinder K. Batra, D. M. Swallow, S. P. Pereira
Muc4 And Muc5ac Are Highly Specific Tumour-Associated Mucins In Biliary Tract Cancer., W. R. Matull, F. Andreola, A. Loh, Z. Adiguzel, M. Deheragoda, U. Qureshi, Surinder K. Batra, D. M. Swallow, S. P. Pereira
Journal Articles: Biochemistry & Molecular Biology
Alterations in epithelial mucin expression are associated with carcinogenesis, but there are few data in biliary tract cancer (BTC). In pancreatic malignancy, MUC4 is a diagnostic and prognostic tumour marker, whereas MUC5AC has been proposed as a sensitive serological marker for BTC. We assessed MUC4 and MUC5AC expression in (i) prospectively collected bile and serum specimens from 72 patients with biliary obstruction (39 BTC) by real-time reverse transcriptase-PCR (qPCR) and western blot analysis, and (ii) 79 archived biliary tissues (69 BTC) by immunohistochemistry. In bile, MUC4 protein was detected in 27% of BTC and 29% of primary sclerosing cholangitis (PSC) …
Early Diagnosis Of Pancreatic Cancer: Neutrophil Gelatinase-Associated Lipocalin As A Marker Of Pancreatic Intraepithelial Neoplasia., N. Moniaux, S. Chakraborty, M. Yalniz, J. Gonzalez, Valerie K. Shostrom, J. Standop, Subodh M. Lele, Michel M. Ouellette, Parviz M. Pour, Aaron Sasson, R. E. Brand, Michael A. Hollingsworth, Maneesh Jain, Surinder K. Batra
Early Diagnosis Of Pancreatic Cancer: Neutrophil Gelatinase-Associated Lipocalin As A Marker Of Pancreatic Intraepithelial Neoplasia., N. Moniaux, S. Chakraborty, M. Yalniz, J. Gonzalez, Valerie K. Shostrom, J. Standop, Subodh M. Lele, Michel M. Ouellette, Parviz M. Pour, Aaron Sasson, R. E. Brand, Michael A. Hollingsworth, Maneesh Jain, Surinder K. Batra
Journal Articles: Biochemistry & Molecular Biology
Pancreatic cancer is a highly lethal malignancy with a dismal 5-year survival of less than 5%. The scarcity of early biomarkers has considerably hindered our ability to launch preventive measures for this malignancy in a timely manner. Neutrophil gelatinase-associated lipocalin (NGAL), a 24-kDa glycoprotein, was reported to be upregulated nearly 27-fold in pancreatic cancer cells compared to normal ductal cells in a microarray analysis. Given the need for biomarkers in the early diagnosis of pancreatic cancer, we investigated the expression of NGAL in tissues with the objective of examining if NGAL immunostaining could be used to identify foci of pancreatic …
Genome-Wide Expression Profiling Reveals Transcriptomic Variation And Perturbed Gene Networks In Androgen-Dependent And Androgen-Independent Prostate Cancer Cells., Ajay P. Singh, Sangeeta Bafna, Kunal Chaudhary, Ganesh Venkatraman, Lynette Smith, James D. Eudy, Sonny L. Johansson, Ming-Fong Lin, Surinder K. Batra
Genome-Wide Expression Profiling Reveals Transcriptomic Variation And Perturbed Gene Networks In Androgen-Dependent And Androgen-Independent Prostate Cancer Cells., Ajay P. Singh, Sangeeta Bafna, Kunal Chaudhary, Ganesh Venkatraman, Lynette Smith, James D. Eudy, Sonny L. Johansson, Ming-Fong Lin, Surinder K. Batra
Journal Articles: Biochemistry & Molecular Biology
Previously, we have developed a unique in vitro LNCaP cell model, which includes androgen-dependent (LNCaP-C33), androgen-independent (LNCaP-C81) and an intermediate phenotype (LNCaP-C51) cell lines resembling the stages of prostate cancer progression to hormone independence. This model is advantageous in overcoming the heterogeneity associated with the prostate cancer up to a certain extent. We characterized and compared the gene expression profiles in LNCaP-C33 (androgen-dependent) and LNCaP-C81 (androgen-independent) cells using Affymetrix GeneChip array analyses. Multiple genes were identified exhibiting differential expression during androgen-independent progression. Among the important genes upregulated in androgen-independent cells were PCDH7, TPTE, TSPY, EPHA3, HGF, MET, EGF, TEM8, etc., …
Recent Advances In Cancer Stem/Progenitor Cell Research: Therapeutic Implications For Overcoming Resistance To The Most Aggressive Cancers., M. Mimeault, Ralph Hauke, Parmender P. Mehta, Surinder K. Batra
Recent Advances In Cancer Stem/Progenitor Cell Research: Therapeutic Implications For Overcoming Resistance To The Most Aggressive Cancers., M. Mimeault, Ralph Hauke, Parmender P. Mehta, Surinder K. Batra
Journal Articles: Biochemistry & Molecular Biology
Overcoming intrinsic and acquired resistance of cancer stem/progenitor cells to current clinical treatments represents a major challenge in treating and curing the most aggressive and metastatic cancers. This review summarizes recent advances in our understanding of the cellular origin and molecular mechanisms at the basis of cancer initiation and progression as well as the heterogeneity of cancers arising from the malignant transformation of adult stem/progenitor cells. We describe the critical functions provided by several growth factor cascades, including epidermal growth factor receptor (EGFR), platelet-derived growth factor receptor (PDGFR), stem cell factor (SCF) receptor (KIT), hedgehog and Wnt/beta-catenin signalling pathways that …
Human Muc4 Mucin Induces Ultra-Structural Changes And Tumorigenicity In Pancreatic Cancer Cells., N. Moniaux, P. Chaturvedi, G. C. Varshney, Jane L. Meza, J. F. Rodriguez-Sierra, J-P Aubert, Surinder K. Batra
Human Muc4 Mucin Induces Ultra-Structural Changes And Tumorigenicity In Pancreatic Cancer Cells., N. Moniaux, P. Chaturvedi, G. C. Varshney, Jane L. Meza, J. F. Rodriguez-Sierra, J-P Aubert, Surinder K. Batra
Journal Articles: Biochemistry & Molecular Biology
MUC4 is a type-1 transmembrane glycoprotein and is overexpressed in many carcinomas. It is a heterodimeric protein of 930 kDa, composed of a mucin-type subunit, MUC4alpha, and a membrane-bound growth factor-like subunit, MUC4beta. MUC4 mRNA contains unique 5' and 3' coding sequences along with a large variable number of tandem repeat (VNTR) domain of 7-19 kb. A direct association of MUC4 overexpression has been established with the degree of invasiveness and poor prognosis of pancreatic cancer. To understand the precise role of MUC4 in pancreatic cancer, we engineered a MUC4 complementary DNA construct, mini-MUC4, whose deduced protein (320 kDa) is …
The Notch Regulator Maml1 Interacts With P53 And Functions As A Coactivator., Yongtong Zhao, Rebecca B. Katzman, Laurie M. Delmolino, Ishfaq Bhat, Ying Zhang, Channabasavaiah B. Gurumurthy, Aleksandra Germaniuk-Kurowska, Honey V. Reddi, Aharon Solomon, Mu-Sheng Zeng, Aisha Kung, Hui Ma, Qingshen Gao, Goberdhan Dimri, Adina Stanculescu, Lucio Miele, Lizi Wu, James D. Griffin, David E. Wazer, Hamid Band, Vimla Band
The Notch Regulator Maml1 Interacts With P53 And Functions As A Coactivator., Yongtong Zhao, Rebecca B. Katzman, Laurie M. Delmolino, Ishfaq Bhat, Ying Zhang, Channabasavaiah B. Gurumurthy, Aleksandra Germaniuk-Kurowska, Honey V. Reddi, Aharon Solomon, Mu-Sheng Zeng, Aisha Kung, Hui Ma, Qingshen Gao, Goberdhan Dimri, Adina Stanculescu, Lucio Miele, Lizi Wu, James D. Griffin, David E. Wazer, Hamid Band, Vimla Band
Journal Articles: Biochemistry & Molecular Biology
Members of the evolutionarily conserved Mastermind (MAM) protein family, including the three related mammalian Mastermind-like (MAML) proteins MAML1-3, function as crucial coactivators of Notch-mediated transcriptional activation. Given the recent evidence of cross-talk between the p53 and Notch signal transduction pathways, we have investigated whether MAML1 may also be a transcriptional coactivator of p53. Indeed, we show here that MAML1 is able to interact with p53. We show that MAML1-p53 interaction involves the N-terminal region of MAML1 and the DNA-binding domain of p53, and we use a chromatin immunoprecipitation assay to show that MAML1 is part of the activator complex that …
An Essential Role Of Human Ada3 In P53 Acetylation., Alo Nag, Aleksandra Germaniuk-Kurowska, Manjari Dimri, Michael A. Sassack, Channabasavaiah B. Gurumurthy, Qingshen Gao, Goberdhan Dimri, Hamid Band, Vimla Band
An Essential Role Of Human Ada3 In P53 Acetylation., Alo Nag, Aleksandra Germaniuk-Kurowska, Manjari Dimri, Michael A. Sassack, Channabasavaiah B. Gurumurthy, Qingshen Gao, Goberdhan Dimri, Hamid Band, Vimla Band
Journal Articles: Biochemistry & Molecular Biology
The p53 tumor suppressor protein functions as a critical component of genotoxic stress response by regulating the expression of effector gene products that control the fate of a cell following DNA damage. Unstressed cells maintain p53 at low levels through regulated degradation, and p53 levels and activity are rapidly elevated upon genotoxic stress. Biochemical mechanisms that control the levels and activity of p53 are therefore of great interest. We and others have recently identified hAda3 (human homologue of yeast alteration/deficiency in activation 3) as a p53-interacting protein and enhancer of p53 activity. Here, we show that endogenous levels of p53 …
Androgen-Regulated Formation And Degradation Of Gap Junctions In Androgen-Responsive Human Prostate Cancer Cells., Shalini Mitra, Lakshmanan Annamalai, Souvik Chakraborty, Kristen E. Johnson, Xiao-Hong Song, Surinder K. Batra, Parmender P. Mehta
Androgen-Regulated Formation And Degradation Of Gap Junctions In Androgen-Responsive Human Prostate Cancer Cells., Shalini Mitra, Lakshmanan Annamalai, Souvik Chakraborty, Kristen E. Johnson, Xiao-Hong Song, Surinder K. Batra, Parmender P. Mehta
Journal Articles: Biochemistry & Molecular Biology
The constituent proteins of gap junctions, called connexins (Cxs), have a short half-life. Despite this, the physiological stimuli that control the assembly of Cxs into gap junctions and their degradation have remained poorly understood. We show here that in androgen-responsive human prostate cancer cells, androgens control the expression level of Cx32-and hence the extent of gap junction formation-post-translationally. In the absence of androgens, a major fraction of Cx32 is degraded presumably by endoplasmic reticulum-associated degradation, whereas in their presence, this fraction is rescued from degradation. We also show that Cx32 and Cx43 degrade by a similar mechanism. Thus, androgens regulate …
The Human Paf Complex Coordinates Transcription With Events Downstream Of Rna Synthesis., Bing Zhu, Subhrangsu S. Mandal, Anh-Dung Pham, Yong Zheng, Hediye Erdjument-Bromage, Surinder K. Batra, Paul Tempst, Danny Reinberg
The Human Paf Complex Coordinates Transcription With Events Downstream Of Rna Synthesis., Bing Zhu, Subhrangsu S. Mandal, Anh-Dung Pham, Yong Zheng, Hediye Erdjument-Bromage, Surinder K. Batra, Paul Tempst, Danny Reinberg
Journal Articles: Biochemistry & Molecular Biology
The yeast PAF (yPAF) complex interacts with RNA polymerase II and coordinates the setting of histone marks associated with active transcription. We report the isolation and functional characterization of the human PAF (hPAF) complex. hPAF shares four subunits with yPAF (hCtr9, hPaf1, hLeo1, and hCdc73), but contains a novel higher eukaryotic-specific subunit, hSki8. RNAi against hSki8 or hCtr9 reduces the cellular levels of other hPAF subunits and of mono- and trimethylated H3-Lys 4 and dimethylated H3-Lys 79. The hSki8 subunit is also a component of the human SKI (hSKI) complex. Yeast SKI complex is cytoplasmic and together with Exosome mediates …
Multiple Roles Of Mucins In Pancreatic Cancer, A Lethal And Challenging Malignancy., N. Moniaux, M. Andrianifahanana, R. E. Brand, Surinder K. Batra
Multiple Roles Of Mucins In Pancreatic Cancer, A Lethal And Challenging Malignancy., N. Moniaux, M. Andrianifahanana, R. E. Brand, Surinder K. Batra
Journal Articles: Biochemistry & Molecular Biology
Mucins are members of an expanding family of large multifunctional glycoproteins. Pancreatic mucins have important biological functions, including the protection, lubrication, and moisturisation of the surfaces of epithelial tissues lining ductal structures within the pancreas. Several lines of evidence support the notion that deregulated mucin production is a hallmark of inflammatory and neoplastic disorders of the pancreas. Herein, we discuss the factors that contribute to the lethality of pancreatic cancer as well as the key role played by mucins, particularly MUC1 and MUC4, in the development and progression of the disease. Aspects pertaining to the aberrant expression and glycosylation of …
Transcriptional Activation Of The Human Prostatic Acid Phosphatase Gene By Nf-Kappab Via A Novel Hexanucleotide-Binding Site., Stanislav Zelivianski, Richard Glowacki, Ming-Fong Lin
Transcriptional Activation Of The Human Prostatic Acid Phosphatase Gene By Nf-Kappab Via A Novel Hexanucleotide-Binding Site., Stanislav Zelivianski, Richard Glowacki, Ming-Fong Lin
Journal Articles: Biochemistry & Molecular Biology
Human prostatic acid phosphatase (PAcP) is a prostate epithelium-specific differentiation antigen. Cellular PAcP functions as a neutral protein tyrosine phosphatase and is involved in regulating androgen-promoted prostate cancer cell proliferation. Despite the fact that the promoter of the PAcP gene has been cloned, the transcriptional factors that regulate PAcP expression remain unidentified. This article describes our analyses of the promoter of the PAcP gene. Deletion analyses of the promoter sequence up to -4893 (-4893/+87) revealed that a 577 bp fragment (-1356/-779) represents the unique positive cis-active element in human prostate cancer cells but not in HeLa cervix carcinoma cells. Interestingly, …
Muc4 Mucin Expression In Human Pancreatic Tumours Is Affected By Organ Environment: The Possible Role Of Tgfbeta2., A. Choudhury, N. Moniaux, A. B. Ulrich, B. M. Schmied, J. Standop, Parviz M. Pour, S. J. Gendler, Michael A. Hollingsworth, J-P Aubert, Surinder K. Batra
Muc4 Mucin Expression In Human Pancreatic Tumours Is Affected By Organ Environment: The Possible Role Of Tgfbeta2., A. Choudhury, N. Moniaux, A. B. Ulrich, B. M. Schmied, J. Standop, Parviz M. Pour, S. J. Gendler, Michael A. Hollingsworth, J-P Aubert, Surinder K. Batra
Journal Articles: Biochemistry & Molecular Biology
MUC4 is highly expressed in human pancreatic tumours and pancreatic tumour cell lines, but is minimally or not expressed in normal pancreas or chronic pancreatitis. Here, we investigated the aberrant regulation of MUC4 expression in vivo using clonal human pancreatic tumour cells (CD18/HPAF) grown either orthotopically in the pancreas (OT) or ectopically in subcutaneous tissue (SC) in the nude mice. Histological examination of the OT and SC tumours showed moderately differentiated and anaplastic morphology, respectively. The OT tumour cells showed metastases to distant lymph nodes and faster tumour growth (P
Expression Of Tumor-Associated Glycoprotein-72 (Tag-72) Antigen In Human Prostatic Adenocarcinomas., Dev Karan, Sonny L. Johansson, Ming-Fong Lin, Surinder K. Batra
Expression Of Tumor-Associated Glycoprotein-72 (Tag-72) Antigen In Human Prostatic Adenocarcinomas., Dev Karan, Sonny L. Johansson, Ming-Fong Lin, Surinder K. Batra
Journal Articles: Biochemistry & Molecular Biology
Tumor-specific antigens are usually defined by monoclonal antibodies (MAbs) and can play critical roles in the diagnosis and therapy of carcinomas. Despite advances in the understanding of the molecular genetics of human prostate carcinomas, therapeutic approaches require that tumor-specific markers, preferably on the cell surface, should be defined. In this study, we examined the expression of an oncofetal antigen tumor-associated glycoprotein-72 (TAG-72) in prostatic adenocarcinomas with a Gleason grade of six or higher. Using a second generation MAb CC49 against TAG-72, immunoreactivity was detected in 88% (29/33) of the prostatic cancer tissues. Occasionally, the benign epithelium showed a very faint …
The Epidermal Growth Factor Receptor From Prostate Cells Is Dephosphorylated By A Prostate-Specific Phosphotyrosyl Phosphatase., Ming-Fong Lin, Gail M. Clinton
The Epidermal Growth Factor Receptor From Prostate Cells Is Dephosphorylated By A Prostate-Specific Phosphotyrosyl Phosphatase., Ming-Fong Lin, Gail M. Clinton
Journal Articles: Biochemistry & Molecular Biology
Human prostatic acid phosphatase (PAcP) has been found to have phosphotyrosyl-protein phosphatase activity (H. C. Li, J. Chernoff, L. B. Chen, and A. Kirschonbaun, Eur. J. Biochem. 138:45-51, 1984; M.-F. Lin and G. M. Clinton, Biochem. J. 235:351-357, 1986) and has been suggested to negatively regulate phosphotyrosine levels, at least in part, by inhibition of tyrosine protein kinase activity (M.-F. Lin and G. M. Clinton, Adv. Protein Phosphatases 4:199-228, 1987; M.-F. Lin, C. L. Lee, and G. M. Clinton, Mol. Cell. Biol. 6:4753-4757, 1986). We investigated the molecular interaction of PAcP with a specific tyrosine kinase, the epidermal growth factor …
Developmental Expression Of Tyrosyl Kinase Activity In Human Serum., Ming-Fong Lin, Joan E. Bailey-Wilson, Robert C. Elston, Gail M. Clinton
Developmental Expression Of Tyrosyl Kinase Activity In Human Serum., Ming-Fong Lin, Joan E. Bailey-Wilson, Robert C. Elston, Gail M. Clinton
Journal Articles: Biochemistry & Molecular Biology
Tyrosine protein kinases, in addition to their roles as viral transforming proteins and growth factor receptors, have been suggested to have specialized functions in tissue specific processes and in differentiation. High levels of soluble tyrosine kinases have been found in human serum and plasma. To determine if the level of tyrosine kinase activity is development tally expressed in human serum, we assayed sera from 214 individuals of different ages from newborns to 90 years. We found that serum tyrosine kinase levels are high in newborns and the levels closely parallel skeletal growth until late adolescence. The serum tyrosine kinase levels …
Tyrosyl Kinase Activity Is Inversely Related To Prostatic Acid Phosphatase Activity In Two Human Prostate Carcinoma Cell Lines., Ming-Fong Lin, Ching-Li Lee, Gail M. Clinton
Tyrosyl Kinase Activity Is Inversely Related To Prostatic Acid Phosphatase Activity In Two Human Prostate Carcinoma Cell Lines., Ming-Fong Lin, Ching-Li Lee, Gail M. Clinton
Journal Articles: Biochemistry & Molecular Biology
Alterations in prostatic acid phosphatase (PAcP), a phosphotyrosyl phosphatase, corresponded to changes in overall tyrosyl kinase activity. PAcP added to extracts of prostate carcinoma cells with a low endogenous level of PAcP activity and elevated tyrosyl kinase activity decreased the tyrosyl kinase activity. On the other hand, when PAcP activity was decreased by the addition of androgens to cells, there was a corresponding increase in tyrosyl kinase activity.