2202 



Schmeer, Rosarii, Sister, O.P. 1967. 



A study of the kinetics of cellular proliferation of the Krebs-2 trans- 

 plantable solid carcinoma and co-existing duodenum as determined by 3 H-T 

 uptake and autoradiography. Biol. Bull. 133(2): 483 (abstract). 



An anticancer principle called mercenene, extracted from the clam Mercenaria, 

 causes oncolysis of Krebs-2 (K-2) carcinoma in CF 1 mice. Cytological light 

 and electron microscopy investigations of tumors from treated animals have 

 failed to reveal the agent's mode of anticancer activity. The cellular 

 kinetics of untreated K-2 carcinoma and duodenum were determined by 3 H-T 

 uptake and autoradiography. A total of 184 mice with a palpable four-day- 

 old tumor was used. Each animal received subcutaneously , at time zero, 

 0.80 pC/g body weight of triated thymidine. Mice were serially sacrificed, 

 three per time interval, from 15 minutes to 24 hr after 3 H-T administration. 

 Autoradiographs of tumor and duodenum sections were prepared and developed 

 after 2 weeks. The mean duration of various phases of the cell cycle is 

 based on mitotic curves derived from the rate of appearance and disappearance 

 of labeled mitoses. For the K-2 carcinoma the mean S period (DNA synthetic 

 time) was 7.5 hrs , G2 (post-DNA synthesis) 2 hrs , Gi (pre-DNA synthesis) 

 zero, M (mitosis) 2.5 hrs, and generation time 12.0 hrs. The co-existing 

 duodenum had a cell cycle essentially similar to that of the duodenum of 

 non- tumor bearing mice. The S period was 7.5 hrs, G 2 equalled one hr, Gi 

 was 7.5 hrs, M was 1.5 hrs, and generation time 15.5 hrs. Presence of tumor 

 does not seem to influence turnover rate of "normal" duodenal population. 

 - J.L.M. 



2203 



Schmeer, Rosarii Sr. 1967. 



Further studies on the utilization of the Krebs-2 carcinoma in an anticancer 

 screening program. J. Cell. Biol. 35(2): 121A (abstract 252). 



An anticancer agent, mercenene, has been extracted from Mercenaria mercenaria. 

 It is effective against Krebs-2 (K-2) carcinoma in vivo, and HeLa and human 

 amnion cells in vitro. Effective crude extracts are prepared by homogenizing 

 the whole clam. The active agent may have a glycopeptide-type structure, 

 possibly associated with a small proportion of protein. K-2 ascites cells 

 were injected subcutaneously in the right axillary region of 4 to 6 week old 

 female CF 1 mice. After a 7-day dosage schedule of the extract, tumors were 

 excised and weighed. The agent caused a 3 to 4 fold regression of tumor as 

 compared with controls. Cytological investigations of similar groups of 

 treated mice, 6 months after termination of treatment, showed complete ab- 

 sence of tumor cells. The cell cycle of transplantable, solid K-2 tumor was 

 determined by 3 H-T uptake and by radioautography . DNA synthetic time, S, 

 was 7.5 hr; G 2 , post-DNA synthetic time, was 2 hr; Gi , pre-DNA synthetic 

 time, was zero; and M, the mitosis phase, was 2.5 hr. Total cell cycle 

 equals 12.0 hr. - J.L.M. 



2204 



Schmeer, Arline C, Sister O.P. 1969. 



Mercenaria clam liver extracts : influence of the HeLa S3 cell cycle. 

 Biol. Bull. 137(2): 385 (abstract). 



An in vitro autoradiographic study was begun to determine if Mercenaria 

 clam liver extracts (mercenene) had any influence on cytokinetics of a HeLa 

 S3 asynchronous cell population and to learn if these extracts were catab- 

 olized in vitro. The data suggest that G2 (post-DNA synthetic time) cells 

 progress into mitosis with a diminished rate with a lag in the entire 

 curve. Cells in S progress into G 2 at a normal rate. DSI for control and 

 experimental cultures was not significantly different. This suggests no 

 direct effect on DNA synthesis. Data indicate catabolism of mercenene in 

 vitro. Since inhibition in G2 has been recorded, it is now possible to 

 determine the mechanism involved in inhibition of new transcriptions observed 

 in HeLa cell population exposed to clam liver extracts. - J.L.M. 



612 



