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The University of Michigan endometrial carcinoma cell line UM-EC-1 was derived from a poorly differentiated endometrial adenocarcinoma of a 66-yr-old white female. Cell cultures were started using both tumor explants and a cell suspension obtained from collagenase-treated tumor tissue. The collagenase-derived cell suspension gave rise to monolayer cultures which grew rapidly from the outset. This subline of UM-EC-1 has now been subcultured more than 50 times. Cells derived from the tumor explants grew more slowly initially, but after a lag phase of 5 to 6 wk, this subline also exhibited rapid logarithmic growth and reached the same growth rate as that of the collagenase-treated cells. The explant subline has been subcultured more than 37 times. The doubling time of both sublines is 24 h under optimal growth conditions. The karyotype of both cell cultures is 43, XX, inv(1)(p32q42), -4, +der(8) t(8;12)(p23.1;q22), del(9)(q11), -13, -13, +t(13;13) (p13;p13), del(18)(q), -19, -22, -22, +t(22;22)(p11;p11). The net result of the chromosome losses and rearrangements was monosomy 4, duplication 8p23.1----qter, deletion 9q11----9qter, duplication 12q22----qter, deletion 18q, and monosomy 19. The t(13;13) and the t(22;22) were dicentric by C-banding. Virtually all of the chromosome changes were stable in multiple passages except that there was mosaicism for chromosome 13. Some cells contained a single copy of 13 and others had t(13;13). The available evidence indicates the t(13;13) is an isochromosome. UM-EC-1 cells produced tumors histologically similar to the original tumor in male, female, and ovariectomized female athymic mice. UM-EC-1 cells express human class I histocompatibility antigens as assessed by binding of antibodies to nonpolymorphic HLA and beta-2-microglobulin antigens. Blood group antigens A and H were absent although the patient is blood type A and these antigens are normally expressed in endometrial glands. A rearrangement involving the region of chromosome nine that carries the ABH locus may be related to the absence of blood group antigen expression by these cells. The E7 membrane antigen, the locus for which resides on the short arm of chromosome 11, was expressed strongly which is consistent with the presence of two intact copies of chromosome 11 in these cells.

Tumor cells from direct harvests and short term cultures were karyotyped from 15 patients with transitional cell carcinoma of the bladder. There were two tumors with an apparently normal diploid karyotype, eight with counts up to 50 and with marker chromosomes, and five with counts of 60 or more and with markers. The median duration between recurrences was 3 months for the near-diploid, and 3 months for the near-polyploid tumors. One patient whose tumor was normal diploid had a recurrence at 5 months and the second patient whose tumor had normal diploid tumor had no recurrence over 15 months. Four tumors (27% of the series) had a rearrangement involving band 3p14: three had +der(5)t(3;5)(p14;p14) and one had +der(6)t(1;3;6)(q21;p14;p23). Duplication 3p14----3pter was observed in four tumors, and deletion 11p15----11pter in five. Three other abnormalities were observed in three cases each: deletion 5p14----5pter, duplication 1q23----1q32 and deletion 6q21----6qter. Trisomy 7 was observed as a sole clonal abnormality in one carcinoma in situ. Thirteen of 15 patients had recurrence of their tumor. Tumor progression (either in stage or grade) was evident in seven recurrent tumors. Among the seven with tumor progression, three had 11p deletion, two had 11p deletion plus 3p duplication, one had 3p duplication, and one had trisomy 7. Four of the five that had 11p deletion underwent cystectomy and three have died. Three of eight near-diploid tumors progressed and four of five near-tetraploid tumors progressed. It will be important to characterize any cytogenetic changes that are of prognostic value, since the categorization of bladder tumors by other methods has been problematic.

The squamous cell carcinoma (SCC) cell lines UM-SCC-17A and -17B were derived, respectively, from the primary laryngeal cancer and a metastatic neck tumor of a patient who failed to respond to radiation therapy but achieved long-term remission after surgery. The karyotypes of both cell lines and a subline of 17A were pseudodiploid and stable in multiple in vitro passages. Several karyotypic abnormalities were common to all three cell lines and therefore represent mutations present in the tumor before the divergence of the metastatic and subline populations whereas those rearrangements observed only in one cell are more likely to be secondary. The shared mutations include: duplication of the short and proximal long arm of chromosome 2, isochromosome 3q, duplication 7, inversion 8, duplication of the distal long arm of 18, and monosomy 21 or ring 21. Each line had different rearrangements involving chromosome 7 that resulted in three copies of most of the short arm being present in both cell lines, except for high passages of 17B, in which one structurally normal 7 was replaced by a dicentric isochromosome, dic(7)(q11.22), resulting in four copies of 7p. The dic(7) may represent an in vitro mutation. An isochromosome 13q was noted in both the stemline and subline of UM-SCC-17A but not in UM-SCC-17B. A del(11p) and an iso(21q) were present only in the 17A subline. The cell lines expressed the membrane antigen phenotype characteristic of squamous cancers although the UM-SCC-17A subline differed with respect to three markers. Of these, the A9 and blood group antigen changes are thought to be associated with progression. The subline, which carried the del(11)(p13-p15.1), also failed to express the E7 antigen mapped to the band 11p13. It is possible that the two apparently normal 11s in this subline carry a point mutation or microscopically undetected deletion involving the E7 antigen locus.