Protected nucleotide sequences in nuclear ribonucleoprotein

The rapidly labeled nuclear ribonucleic acid in human carcinoma cells which is protected by protein from digestion by staphylococcal nuclease (EC 3.1.4.7) has been investigated. A simple and discrete sequence specificity was not found, but the protected RNA fragments are rich in G + C and were shown by fingerprinting to comprise a nonrandom subset of all heterogeneous nuclear ribonucleic acid (hnRNA) sequences enriched in the sequences AGC, GGC, AGGC, and GAGC. There was no detectable enrichment for dougble-stranded RNA in the protected fraction. These data provide the first evidence that the association of any protein with hnRNA is nonrandom with respect to nucleotide sequence.

Direct tissue isoelectric focusing in agarose

We are isoelectric focusing small amounts of tissues placed directly on electroendosmosis-free agarose gels instead of using the saline extracts of tissue homogenates. More numerous proteins are extracted during isoelectric focusing of the solid tissues than present in the same tissues.

Response of exponentially growing, stationary-phase, and synchronized cultured human colon carcinoma cells to treatment with nitrosourea derivatives

The lethal effects of two nitrosourea derivatives, 1,3-bis(2-chloroethyl)-1-nitrosourea and 4-[3-(2-chloroethyl)-3-nitrosoureido]-cis-cyclohexanecarboxylic acid, on a continuous line of human colon carcinoma cells (LoVo cells) were investigated. The survival response of exponentially growing and stationary-phase LoVo cells to both drugs were of the threshold exponential type. Survival was identical whether drugs were dissolved in medium or in Hanks' balanced salt solution. In contrast to previous results obtained for human lymphoma cells, 1,3-bis(2-chloroethyl)-1-nitrosourea exerted a progressively greater killing effect on LoVo cells as the incubation time was prolonged, while 4-[3-(2-chloroethyl)-3-nitrosoureido]-cis-cyclohexane-carboxylic acid, under similar circumstances presented decreased lethality in comparison to both 1,3-bis(2-chloroethyl)-1-nitrosourea and the effect previously observed for the lymphoma cells. Although no recovery from potentially lethal damage was noted for both exponentially growing and stationary-phase cells treated with each agent, in split-dose experiments, LoVo cells were able to recover from sublethal damage. No significant cell cycle stage dependent differences in killing ability were observed for the two agents.

[Gastrointestinal localizations of malignant lymphomas]

Lymphoma of the alimentary canal is somewhat rare. It has no unusual features and few characteristics, with the result that its clinical, radiological and endoscopic diagnosis is problematic, since its lesions may readily be confused by other neoplastic or inflammatory forms. The difficulty is, of course, primarily felt in the case of primary sites, since the co-existence of other lymphomatous tissues facilitates diagnosis. It is suggested that surgeons should be aware of the existence and treatment of these forms. 13 cases collected from 25 laparosplenectomies for staging since 1971 are presented. Four patients had primary lesions, whereas generalised lymphoma was present in the remainder. Nine patients are still alive after treatment.

Multiple primary cancers involving the lung

Of 150 consecutive patients with resectable bronchogenic carcinoma, 11 were found to have multiple primary tumours of the respiratory tract. Five patients had more than one primary tumour of the lung and six had previously received treatment for carcinoma of the larynx. In the same group of 150 patients, 14 had one or more cancers involving other organs. The appearance of a new solitary lung lesion in a patient with another cancer demands special attention to determine the exact diagnosis and to decide upon the best method of treatment. Physicians should be aware that such a lung lesion may represent a new primary lung cancer rather than a metastasis. The criteria are defined for the pathological definition of two separate primary tumours in these cases.

[Frequency, time and type of metastasis of different transplantable tumors in mice]

The character of metastasis of 9 strains of transplantable mouse tumours in conventional subcutaneous inoculation was studied. There were differences in the frequency, intensity, and types of metastasis of different tumours. Periods of onset of metastases of Lewis lung carcinoma and RL-67, and also of sarcoma-37 were established. Sarcoma, Lewis and RL-67 lung carcinomas, adenocarcinoma of the colon AKATOL, Cloudman's melanoma and B-16 metastasized most intensively. Sarcoma-37 metastasizing into the regional and remote lymph nodes, Lewis lung carcinoma and melanomas metastasizing into the lungs, RL-67 lung carcinoma metastasizing into the lungs, kidneys, adrenal glands, ovaries, the heart, and also adenocarcinoma of the colon AKATOL metastasizing into the lymph nodes and the liver can be used as models for the research in the field of drug action upon metastases and the metastasis process.

Leiomyosarcoma metastatic to the brain

A rare instance of leiomyosarcoma metastatic to the brain in a 60-year-old male is presented. The primary site was in the gastrointestinal tract. Previously reported cases of similar nature are reviewed.

Treatment of symptomatic metastatic cancer to the liver from primary colon and rectal cancer by the intraarterial administration of chemotherapy and radioactive isotopes

Sixty-five patients were referred for treatment with symptoms resulting from metastatic cancer to the liver from the GI tract. Two groups of patients were analyzed. The first group of 40 patients were subjected to a laparotomy and insertion of a catheter into the hepatic artery and a second group had the catheter inserted percutaneously and a bolus of cancer chemotherapeutic agents injected into the catheter. In both groups, chemotherapy in the form of 5-fluorouracil was supplemented by internal irradiation delivered from the intraarterial administration of Yttrium 90 microspheres. Forty percent of the patients who had an indwelling catheter performed at celiotomy manifested an objective response and in 60% a significant subjective improvement occurred. In the 25 patients whose catheter was inserted percutaneously, the response rate was roughly similar, in that 35% demonstrated an objective response and 65% demonstrated a subjective response.