0 14 Constitutively constitutively RB 15 24 activated activate VBN 25 33 Jak-STAT jak-stat JJ 34 41 pathway pathway NN 42 44 in in IN 45 46 T t NN 47 52 cells cell NNS 53 64 transformed transform VBN 65 69 with with IN 70 76 HTLV-I HTLV-I NNP 76 77 . . . 79 84 Human human JJ 85 86 T t NN 87 91 cell cell NN 92 104 lymphotropic lymphotropic JJ 105 110 virus virus NN 111 112 I i CD 113 114 ( ( ( 114 120 HTLV-I HTLV-I NNP 120 121 ) ) ) 122 124 is be VBZ 125 128 the the DT 129 140 etiological etiological JJ 141 146 agent agent NN 147 150 for for IN 151 156 adult adult JJ 157 158 T t NN 159 163 cell cell NN 164 172 leukemia leukemia NN 173 176 and and CC 177 185 tropical tropical JJ 186 193 spastic spastic JJ 194 205 paraparesis paraparesis NN 206 207 ( ( ( 207 211 also also RB 212 218 termed term VBN 219 236 HTLV-I-associated htlv-i-associated JJ 237 247 myelopathy myelopathy NN 247 248 ) ) ) 248 249 . . . 250 265 HTLV-I-infected htlv-i-infected JJ 266 276 peripheral peripheral JJ 277 282 blood blood NN 283 284 T t NN 285 290 cells cell NNS 291 298 exhibit exhibit VBP 299 301 an an DT 302 309 initial initial JJ 310 315 phase phase NN 316 318 of of IN 319 332 interleukin-2 interleukin-2 NN 333 334 ( ( ( 334 349 IL-2)-dependent il-2)-dependent JJ 350 356 growth growth NN 356 357 ; ; : 358 362 over over IN 363 367 time time NN 367 368 , , , 369 371 by by IN 372 374 an an DT 375 382 unknown unknown JJ 383 392 mechanism mechanism NN 392 393 , , , 394 397 the the DT 398 403 cells cell NNS 404 410 become become VBP 411 427 IL-2-independent il-2-independent JJ 427 428 . . . 429 436 Whereas whereas IN 437 440 the the DT 441 444 Jak Jak NNP 445 452 kinases kinase NNS 453 457 Jak1 Jak1 NNP 458 461 and and CC 462 466 Jak3 Jak3 NNP 467 470 and and CC 471 474 the the DT 475 481 signal signal NN 482 492 transducer transducer NN 493 496 and and CC 497 506 activator activator NN 507 509 of of IN 510 523 transcription transcription NN 524 532 proteins protein NNS 533 538 Stat3 Stat3 NNP 539 542 and and CC 543 548 Stat5 Stat5 NNP 549 552 are be VBP 553 562 activated activate VBN 563 565 in in IN 566 572 normal normal JJ 573 574 T t NN 575 580 cells cell NNS 581 583 in in IN 584 592 response response NN 593 595 to to TO 596 600 IL-2 il-2 NN 600 601 , , , 602 606 this this DT 607 616 signaling signaling NN 617 624 pathway pathway NN 625 628 was be VBD 629 643 constitutively constitutively RB 644 653 activated activate VBN 654 656 in in IN 657 675 HTLV-I-transformed htlv-i-transformed JJ 676 681 cells cell NNS 681 682 . . . 683 685 In in IN 686 701 HTLV-I-infected htlv-i-infected JJ 702 706 cord cord NN 707 712 blood blood NN 713 724 lymphocytes lymphocyte NNS 724 725 , , , 726 729 the the DT 730 740 transition transition NN 741 745 from from IN 746 760 IL-2-dependent il-2-dependent JJ 761 763 to to TO 764 780 IL-2-independent il-2-independent JJ 781 787 growth growth NN 788 798 correlated correlate VBD 799 803 with with IN 804 807 the the DT 808 819 acquisition acquisition NN 820 822 of of IN 823 824 a a DT 825 839 constitutively constitutively RB 840 849 activated activate VBN 850 858 Jak-STAT jak-stat JJ 859 866 pathway pathway NN 866 867 , , , 868 873 which which WDT 874 882 suggests suggest VBZ 883 887 that that IN 888 892 this this DT 893 900 pathway pathway NN 901 913 participates participate VBZ 914 916 in in IN 917 932 HTLV-I-mediated htlv-i-mediated JJ 933 934 T t NN 935 939 cell cell NN 940 954 transformation transformation NN 954 955 . . .