Elizabeth W. Chu

Melatonin, a Pineal Substance: Effect on the Rat Ovary

Daily injection of microgram amounts of melatonin in rats decreased the incidence of estrus and reduced ovarian weight. Circulating melatonin was selectively taken up and retained by the ovary and pineal gland; this effect was reduced by exposure of rats to constant light. A single injection of melatonin lowered the incidence of estrus among rats exposed to constant light.

Cytogenetic studies in ovarian cancer

Cytogenetic studies of ovarian cancer have been conducted in the Medicine Branch, NCI, National Institutes of Health for 5 years. A total of 72 patients were studied by direct preparation and/or 1- to 3-day short-term culture of ascites (86 samples), pleural fluid (4 samples), and tumor (2 samples). Repeat examinations (1-24 months later) were performed in 7 of the 72 patients. Forty-four patients (62%) were successfully analyzed with banding techniques: 6 patients had adenocarcinoma, 7 had serous adenocarcinoma, 13 had serous papillary adenocarcinoma, 7 had serous papillary cystadenocarcinoma, 2 had mucinous adenocarcinoma, 6 had undifferentiated or poorly differentiated adenocarcinoma, 1 had clear cell adenocarcinoma, and 2 were not classified. Of these 44 patients, 29 had received prior chemotherapy, 14 were untreated, and in 1 patient the treatment status was unknown. Aneuploidy was observed in all patients and there was considerable variation in the chromosome numbers (even within single samples), often ranging from diploidy to triploidy to tetraploidy. All 44 patients had numerical abnormalities and 39 had structural abnormalities. The chromosomes most frequently involved in structural abnormalities (in decreasing order according to the number of patients involved) were #1, #3, #2, #4, #9, #10, #15, #19, #6, and #11; the least involved chromosomes were #21 and #5. Clone formation and the number of chromosomes involved in structural abnormalities increased with duration of disease and were more extensive in patients treated with chemotherapy than in patients treated with surgery alone. Our data did not show a deletion of chromosome #6 (6q-) to be specific for ovarian cancer.

Lymphokine-activated killer (LAK) cells. Analysis of factors relevant to the immunotherapy of human cancer

Lymphokine‐activated killer (LAK) cells can be generated by incubating fresh peripheral blood lymphocytes (PBL) in Interleukin‐2 (IL‐2). LAK cells kill fresh autologous and allogeneic human tumor cells in vitro. This study analyzes aspects of LAK cells that make them a promising candidate for the adoptive immunotherapy of human cancer. LAK cells can be generated from PBL of normal individuals and tumor‐bearing patients. Pure, recombinant IL‐2 generates LAK cells capable of killing a wide variety of tumors including sarcomas and cancers of the colon, pancreas, adrenal gland, and esophagus. Thirty‐six of 41 (88%) fresh, noncultured, human tumor cell suspensions prepared from surgical specimens were lysed by LAK cells in a standard 4‐hour chromium‐release assay. Normal PBL were not killed. LAK cells can be expanded in vitro for periods longer than 2 months, potentially more than 1020‐fold, while maintaining lytic ability. These results and the demonstrated efficacy of LAK cells in the therapy of murine tumors make LAK cells a candidate for clinical use in the adoptive immunotherapy of human cancer. Cancer 55:1327‐1333, 1985.

Polyploidy road to therapy‐induced cellular senescence and escape

Therapy‐induced cellular senescence (TCS), characterized by prolonged cell cycle arrest, is an in vivo response of human cancers to chemotherapy and radiation. Unfortunately, TCS is reversible for a subset of senescent cells, leading to cellular reproliferation and ultimately tumor progression. This invariable consequence of TCS recapitulates the clinical treatment experience of patients with advanced cancer. We report the findings of a clinicopathological study in patients with locally advanced non‐small cell lung cancer demonstrating that marker of in vivo TCS following neoadjuvant therapy prognosticate adverse clinical outcome. In our efforts to elucidate key molecular pathways underlying TCS and cell cycle escape, we have previously shown that the deregulation of mitotic kinase Cdk1 and its downstream effectors are important mediators of survival and cell cycle reentry. We now report that aberrant expression of Cdk1 interferes with apoptosis and promotes the formation of polyploid senescent cells during TCS. These polyploid senescent cells represent important transition states through which escape preferentially occurs. The Cdk1 pathway is in part modulated differentially by p21 and p27 two members of the KIP cyclin‐dependent kinase inhibitor family during TCS. Altogether, these studies underscore the importance of TCS in cancer therapeutics.

Isolation of a continuous epithelioid cell line, HBT-3, from a human breast carcinoma.

Summary A continuous line of human breast carcinoma cells, HBT-3, was established in culture following collagenase treatment of a mucus producing adenocarcinoma. The cells are epithelioid in appearance, multiply rapidly, have a cloning efficiency of approximately 70%, and exhibit an abnormal karyotype with a mode of 66-69 chromosomes/cell and 3 markers. Tumor material and pathological diagnosis were provided through the courtesy of Dr. J. D. Mashburn, Director of Laboratories, Washington Sanitarium and Hospital, Takoma Park, MD. Dr. C. S. Stulberg, Senior Research Associate, The Child Research Center of Michigan, Detroit, kindly performed the immunofluorescence cell typing tests. A portion of these studies was carried out at Bionetics Research Laboratories, Inc., Bethesda, MD, under contract 69-2160 from the Special Virus Cancer Program of the National Cancer Institute. Technical assistance of Cathy K. Smith, Nancy Tuttle Fuller, and Diane Robertson is gratefully acknowledged. The authors thank Drs. Peter J. Fischinger and Tadao Aoki of the National Cancer Institute for their advice and many helpful discussions.

Differential Diagnostic Significance of The Paucity of HLA-I Antigens on Metastatic Breast Carcinoma Cells in Effusions

Distinction between benign reactive mesothelial cells and metastatic breast adenocarcinoma cells in effusions from patients with a known prior history of breast cancer is not the easiest task in diagnostic pathology. Here, we report the usefulness of testing the expression of class I HLA antigens (HLA A, B, C) in this respect. Cytospins were prepared from effusions of patients without the history of breast cancer (5 cases) and from effusions of patients with infiltrating ductal carcinoma (11 cases). Three effusions from cancerous patients were not malignant cytologically. The expression of HLA-A, B, C, HLA-DR and β2-microglobulin as well as the macrophage antigen, CD14, was evaluated by immunocytochemistry. In 10 of 11 effusions the cytologically malignant cells expressed very weak or undetectable HLA-A,B,C as compared to the mesothelial cells and macrophages. The paucity of expression of HLA-A, B, C was detectable in those 3 cases where a definitive cytological diagnosis of malignancy could not be established. In contrast, mesothelial cells and macrophages from all samples were uniformly and strongly positive for both HLA-A, B, C and β2-microglobulin. We conclude that the paucity of HLA-I antigens provides a marker helpful in distinguishing metastatic breast carcinoma cells from reactive mesothelial cells in effusions.

Abstract 1242: Induction and targeting of polyploid senescent cells in cancer therapeutics

Proceedings: AACR 102nd Annual Meeting 2011‐‐ Apr 2‐6, 2011; Orlando, FL Therapy-induced cellular senescence (TCS), an emerging concept in cancer therapeutics, describes an in vivo response of human tumors to chemotherapy and radiation. These treatments elicit a coordinated response that results in prolonged cell cycle arrest, characteristic senescence morphology and expression of senescence-specific markers. In the past decade, a growing body of evidence has supported the hypothesis that “senescence response occurs in treated human cancers and the response is reversible.” We now present evidence that TCS may be adverse to cancer therapeutics based on a clinicopatholgical study conducted in patients with advanced non-small cell lung cancer following induction therapy prior to surgery. To further define how a subpopulation of senescent cells could escape terminal arrest, our work now implicates a polyploid state through which senescent cells can survive and eventually resume proliferation. In H1299 lung cancer cells, we show that mitotic kinase Cdk1 facilitates endoreplication and formation of polyplid senescent cells (PSCs) following chemotherapy as the genetic modulation of Cdk1 activity profoundly affect the prevalence of these polyploid cells. Importantly, senescence escape occurs from the PSCs at 2.5 times the frequency of escape observed from diploid (2/4n) cells through novel non-canonical cell division mechanisms. Furthermore, we also demonstrate distinct functions of p21 and p27, two members of KIP family in TCS. While both interact with endogenous cyclin B1-Cdk1 complex in senescent cells, only p27 directly inhibits Cdk1 kinase activity and modulates PSC formation, whereas the knockdown of p21 leads to massive apoptosis. Finally, we show that statins, HMG-CoA inhibitors, currently approved for treatment of dyslipidemia down-regulate several key targets of the Cdk1 pathway, including Cdk1 itself, cyclin B1, and survivin, while up-regulating p27. Statins both decrease polyploid cells and abrogate escape of several cancer cell lines from TCS. Altogether, our work here challenges the current cancer treatment paradigm and supports the incorporation of novel strategies to enforce irreversible cell cycle exit in senescent tumor cells following treatment. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 1242. doi:10.1158/1538-7445.AM2011-1242

Production of Tumors in Syrian Hamsters After Oral Administration of Polyoma Virus

Summary Polyoma virus was administered orally to young Syrian hamsters twice weekly for 68 weeks. Four of the 20 animals developed subcutaneous sarcomas 14, 18, 18 and 44 weeks after initiation of the experiment. The tumors were similar to those produced in hamsters by subcutaneous inoculation of the virus. The 4 animals with subcutaneous tumors and 7 animals from the infected groups without subcutaneous tumors have been necropsied, and no evidence of primary tumors of the gastrointestinal tract has been found. No tumors have been observed in the remaining animals in the group fed virus and in 10 control animals given tissue culture fluid free of virus. These findings indicate that although oral administration of an oncogenic virus may not result in primary tumors of the gastrointestinal tract, subcutaneous tumors may be produced.