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  1. Article: Expression of H-ras and c-myc protooncogenes in isolated gamma-glutamyl transpeptidase-positive rat hepatocytes and in hepatocellular carcinomas induced by diethylnitrosamine.

    Beer, D G / Schwarz, M / Sawada, N / Pitot, H C

    Cancer research

    1986  Volume 46, Issue 5, Page(s) 2435–2441

    Abstract: ... for Northern blot hybridizations. The blots were probed with 32P-labeled c-myc, H-ras, and albumin DNAs. The results ... in either the size or amount of mRNA transcripts for the c-myc and H-ras protooncogenes. Increased expression of c ... Sprague-Dawley rats were subjected to a two-thirds partial hepatectomy, followed 18 h later by a single intragastric ...

    Abstract The appearance of gamma-glutamyl transpeptidase (GGT) in focal areas of hepatocytes is a widely used histochemical marker for the identification of preneoplastic cell populations. The characterization of these GGT-positive preneoplastic cells in relation to possible alterations in protooncogene expression may help define cellular changes occurring during the early stages of hepatocarcinogenesis. Female Sprague-Dawley rats were subjected to a two-thirds partial hepatectomy, followed 18 h later by a single intragastric administration of 30 mg of diethylnitrosamine per kg and subsequent feeding of a diet containing 0.05% phenobarbital for 6 or 11 mo. Primary cell suspensions were obtained after the perfusion of liver with collagenase. Cell debris and nonviable cells were removed with multiple washes and a Percoll gradient step. GGT-positive hepatocytes were enriched from the cell suspension by adherence to an affinity-purified GGT antibody affixed to Petri dishes. These dishes allowed the selective adherence and collection of up to 2.28 X 10(6) GGT-positive cells per liver. The starting cell population and the isolated GGT-positive and -negative cells were then used for subsequent analysis. RNA was prepared from the cell isolates and from hepatocellular carcinomas induced with the same diethylnitrosamine and phenobarbital regimen as that used to induce GGT-positive foci; 10 micrograms of total cellular RNA were used for Northern blot hybridizations. The blots were probed with 32P-labeled c-myc, H-ras, and albumin DNAs. The results indicate that GGT-positive hepatocytes do not differ from the other hepatocyte populations in either the size or amount of mRNA transcripts for the c-myc and H-ras protooncogenes. Increased expression of c-myc and H-ras was observed in some malignant lesions and may represent a secondary alteration occurring during the multistage process of hepatocarcinogenesis.
    MeSH term(s) Albumins/genetics ; Animals ; Female ; Gene Expression Regulation/drug effects ; Liver/cytology ; Liver/physiology ; Liver Neoplasms/pathology ; Liver Neoplasms/physiopathology ; Liver Neoplasms, Experimental/pathology ; Liver Neoplasms, Experimental/physiopathology ; Phenobarbital/pharmacology ; Proto-Oncogenes ; RNA, Messenger/genetics ; Rats ; gamma-Glutamyltransferase/metabolism
    Chemical Substances Albumins ; RNA, Messenger ; gamma-Glutamyltransferase (EC 2.3.2.2) ; Phenobarbital (YQE403BP4D)
    Language English
    Publishing date 1986-05
    Publishing country United States
    Document type Journal Article ; Research Support, U.S. Gov't, P.H.S.
    ZDB-ID 1432-1
    ISSN 1538-7445 ; 0008-5472
    ISSN (online) 1538-7445
    ISSN 0008-5472
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  2. Article: Estrogen Receptor-α Suppresses Liver Carcinogenesis and Establishes Sex-Specific Gene Expression.

    O'Brien, Mara H / Pitot, Henry C / Chung, Sang-Hyuk / Lambert, Paul F / Drinkwater, Norman R / Bilger, Andrea

    Cancers

    2021  Volume 13, Issue 10

    Abstract: Estrogen protects females from hepatocellular carcinoma (HCC). To determine whether this protection is mediated by classic estrogen receptors, we tested HCC susceptibility in estrogen receptor-deficient mice. In contrast to a previous study, we found ... ...

    Abstract Estrogen protects females from hepatocellular carcinoma (HCC). To determine whether this protection is mediated by classic estrogen receptors, we tested HCC susceptibility in estrogen receptor-deficient mice. In contrast to a previous study, we found that diethylnitrosamine induces hepatocarcinogenesis to a significantly greater extent when females lack
    Language English
    Publishing date 2021-05-13
    Publishing country Switzerland
    Document type Journal Article
    ZDB-ID 2527080-1
    ISSN 2072-6694
    ISSN 2072-6694
    DOI 10.3390/cancers13102355
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  3. Article ; Online: Falls: descriptive rates and circumstances in age-unspecified patients with locally advanced esophageal cancer.

    Childs, Daniel S / Yoon, Harry H / Eiring, Rachel A / Jin, Zhaohui / Jochum, Jacob A / Pitot, Henry C / Jatoi, Aminah

    Supportive care in cancer : official journal of the Multinational Association of Supportive Care in Cancer

    2020  Volume 29, Issue 2, Page(s) 733–739

    Abstract: Purpose: Falls can occur in older cancer patients, but few studies have examined falls in an age-unspecified group of patients with locally advanced esophageal cancer. Because these patients are often administered neuropathy-inducing agents, are weak, ... ...

    Abstract Purpose: Falls can occur in older cancer patients, but few studies have examined falls in an age-unspecified group of patients with locally advanced esophageal cancer. Because these patients are often administered neuropathy-inducing agents, are weak, and can develop orthostatic symptoms, examining falls appears relevant.
    Methods: Electronic medical records were used to examine falls and their circumstances in locally advanced esophageal cancer patients treated with chemotherapy and radiation and often surgery.
    Results: Among 300 patients, 62 (21%) suffered a fall, yielding 6 falls per 100 patient years. The median age at first fall was 64 years (range 31 to 83). The median time from cancer diagnosis to first fall was 11 months (range 0 to 107). Forty-two patients (68%) who fell had active cancer; 20 (32%) were cancer-free. Fall-related injuries occurred in 42 patients and included fractures, hematomas, and other musculoskeletal events. Eighteen patients (29%) fell repeatedly. Neuropathy, general weakness, and orthostatic symptoms were associated with falls ("He does state his neuropathy is more bothersome…. He did have a fall last week…." "He has been increasingly weak to the point where he fell down last week…." "Upon rising… [he] felt like somebody had put a sheet over his eyes, felt very lightheaded, and fell to the floor…."). At times, falls occurred under commonplace circumstances, such as slipping on ice or tripping on an underfoot pet.
    Conclusion: Regardless of patient age, clinicians should remain vigilant for fall risk in adult patients with locally advanced esophageal cancer.
    MeSH term(s) Accidental Falls/statistics & numerical data ; Adult ; Age Factors ; Aged ; Aged, 80 and over ; Electronic Health Records ; Esophageal Neoplasms/epidemiology ; Esophageal Neoplasms/pathology ; Female ; Fractures, Bone/epidemiology ; Humans ; Male ; Middle Aged ; Risk Factors
    Language English
    Publishing date 2020-05-24
    Publishing country Germany
    Document type Journal Article
    ZDB-ID 1134446-5
    ISSN 1433-7339 ; 0941-4355
    ISSN (online) 1433-7339
    ISSN 0941-4355
    DOI 10.1007/s00520-020-05511-z
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  4. Article: ALTERED TEMPLATE STABILITY: THE MOLECULAR MASK OF MALIGNANCY?

    PITOT, H C

    Perspectives in biology and medicine

    2003  Volume 7, Page(s) 50–70

    MeSH term(s) DNA ; DNA, Neoplasm ; Genetics, Medical ; Masks ; Metabolism ; Neoplasms/etiology ; RNA ; RNA, Neoplasm
    Chemical Substances DNA, Neoplasm ; RNA, Neoplasm ; RNA (63231-63-0) ; DNA (9007-49-2)
    Language English
    Publishing date 2003-08-14
    Publishing country United States
    Document type Journal Article
    ZDB-ID 80373-x
    ISSN 1529-8795 ; 0031-5982
    ISSN (online) 1529-8795
    ISSN 0031-5982
    DOI 10.1353/pbm.1964.0004
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  5. Article: Pathways of progression in hepatocarcinogenesis.

    Pitot, H C

    Lancet (London, England)

    2001  Volume 358, Issue 9285, Page(s) 859–860

    MeSH term(s) Animals ; Hepatitis B/complications ; Humans ; Karyotyping ; Liver Neoplasms/etiology ; Liver Neoplasms/genetics ; Molecular Biology
    Language English
    Publishing date 2001-09-15
    Publishing country England
    Document type Journal Article ; Review
    ZDB-ID 3306-6
    ISSN 1474-547X ; 0140-6736 ; 0023-7507
    ISSN (online) 1474-547X
    ISSN 0140-6736 ; 0023-7507
    DOI 10.1016/S0140-6736(01)06038-X
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  6. Article: Animal models of neoplastic development.

    Pitot, H C

    Developments in biologicals

    2001  Volume 106, Page(s) 53–7; discussion 57–9, 143–60

    Abstract: The basic animal model for neoplastic development used by regulatory agencies is the two-year chronic bioassay developed more than 30 years ago and based on the presumed mechanism of action of a few potential chemical carcinogens. Since that time, a ... ...

    Abstract The basic animal model for neoplastic development used by regulatory agencies is the two-year chronic bioassay developed more than 30 years ago and based on the presumed mechanism of action of a few potential chemical carcinogens. Since that time, a variety of other model carcinogenic systems have been developed, usually involving shorter duration, single organ endpoints, multistage models, and those in genetically-engineered mice. The chronic bioassay is still the "gold standard" of regulatory agencies despite a number of deficiencies, while in this country the use of shorter term assays based on single organ endpoints has not been popular. The multistage model of carcinogenesis in mouse epidermis actually preceded the development of the chronic two-year bioassay, but it was not until multistage models in other organ systems were developed that the usefulness of such systems became apparent. Recently, several genetically-engineered mouse lines involving mutations in proto-oncogenes and tumour suppressor genes have been proposed as additional model systems for use in regulatory decisions. It is likely that a combination of several of these model systems may be most useful in both practical and basic applications of cancer prevention and therapy.
    MeSH term(s) Animals ; Biological Assay ; Carcinogenicity Tests ; Cell Transformation, Neoplastic ; Disease Models, Animal ; Mice ; Mice, Transgenic
    Language English
    Publishing date 2001
    Publishing country Switzerland
    Document type Journal Article
    ISSN 1424-6074
    ISSN 1424-6074
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  7. Article ; Online: Role of Ultraviolet Radiation in Papillomavirus-Induced Disease.

    Uberoi, Aayushi / Yoshida, Satoshi / Frazer, Ian H / Pitot, Henry C / Lambert, Paul F

    PLoS pathogens

    2016  Volume 12, Issue 5, Page(s) e1005664

    Abstract: Human papillomaviruses are causally associated with 5% of human cancers. The recent discovery of a papillomavirus (MmuPV1) that infects laboratory mice provides unique opportunities to study the life cycle and pathogenesis of papillomaviruses in the ... ...

    Abstract Human papillomaviruses are causally associated with 5% of human cancers. The recent discovery of a papillomavirus (MmuPV1) that infects laboratory mice provides unique opportunities to study the life cycle and pathogenesis of papillomaviruses in the context of a genetically manipulatable host organism. To date, MmuPV1-induced disease has been found largely to be restricted to severely immunodeficient strains of mice. In this study, we report that ultraviolet radiation (UVR), specifically UVB spectra, causes wild-type strains of mice to become highly susceptible to MmuPV1-induced disease. MmuPV1-infected mice treated with UVB develop warts that progress to squamous cell carcinoma. Our studies further indicate that UVB induces systemic immunosuppression in mice that correlates with susceptibility to MmuPV1-associated disease. These findings provide new insight into how MmuPV1 can be used to study the life cycle of papillomaviruses and their role in carcinogenesis, the role of host immunity in controlling papillomavirus-associated pathogenesis, and a basis for understanding in part the role of UVR in promoting HPV infection in humans.
    MeSH term(s) Animals ; Carcinoma, Squamous Cell/virology ; Disease Models, Animal ; Mice ; Papilloma/virology ; Papillomaviridae ; Papillomavirus Infections/complications ; Skin Neoplasms/virology ; Ultraviolet Rays/adverse effects
    Language English
    Publishing date 2016-05-31
    Publishing country United States
    Document type Journal Article ; Research Support, N.I.H., Extramural
    ZDB-ID 2205412-1
    ISSN 1553-7374 ; 1553-7366
    ISSN (online) 1553-7374
    ISSN 1553-7366
    DOI 10.1371/journal.ppat.1005664
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  8. Article: Hepatocyte death in hepatocarcinogenesis.

    Pitot, H C

    Hepatology (Baltimore, Md.)

    1998  Volume 28, Issue 1, Page(s) 1–5

    MeSH term(s) Animals ; Apoptosis/physiology ; Cell Death/physiology ; Gene Expression/physiology ; Humans ; Liver/pathology ; Liver Neoplasms/etiology ; Liver Neoplasms/pathology
    Language English
    Publishing date 1998-07
    Publishing country United States
    Document type Journal Article ; Review
    ZDB-ID 604603-4
    ISSN 1527-3350 ; 0270-9139
    ISSN (online) 1527-3350
    ISSN 0270-9139
    DOI 10.1002/hep.510280101
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  9. Article: US pivotal studies of irinotecan in colorectal carcinoma.

    Pitot, H C

    Oncology (Williston Park, N.Y.)

    1998  Volume 12, Issue 8 Suppl 6, Page(s) 48–53

    Abstract: Phase I trials of irinotecan (CPT-11 [Camptosar]), conducted at Johns Hopkins and the University of Texas, San Antonio, demonstrated some activity in patients with refractory advanced cancer. Three pivotal phase II studies of irinotecan in advanced ... ...

    Abstract Phase I trials of irinotecan (CPT-11 [Camptosar]), conducted at Johns Hopkins and the University of Texas, San Antonio, demonstrated some activity in patients with refractory advanced cancer. Three pivotal phase II studies of irinotecan in advanced colorectal carcinoma were conducted at The University of Texas, San Antonio, Mayo/North Central Cancer Treatment Group (NCCTG), and the CPT-11 Study Group in a total of 304 patients. All patients had received prior fluorouracil (5-FU) chemotherapy, and over 90% had progressed while on treatment within the last 6 months. The initial starting dose of irinotecan ranged from 100 to 150 mg/m2. The overall response rate was 12.8% (95% confidence interval, 9.1% to 16.6%) with a 15% response rate at a recommended starting dose of 125 mg/m2. The response durations and overall median survivals were similar in the three studies. The principal toxicities included diarrhea, nausea, vomiting, and neutropenia. Severe diarrhea was limited by use of an intensive loperamide regimen and appropriate dose modification. The three pivotal studies of irinotecan in advanced colorectal carcinoma demonstrate consistent response rates and duration, with manageable toxicity. Future studies will focus on the use of irinotecan in chemotherapeutically naive colorectal carcinoma, the adjuvant treatment of colon carcinoma, combination chemotherapeutic regimens, and treatment of other malignant diseases.
    MeSH term(s) Adult ; Aged ; Aged, 80 and over ; Antimetabolites, Antineoplastic/therapeutic use ; Antineoplastic Agents, Phytogenic/adverse effects ; Antineoplastic Agents, Phytogenic/therapeutic use ; Camptothecin/adverse effects ; Camptothecin/analogs & derivatives ; Camptothecin/therapeutic use ; Clinical Trials, Phase I as Topic ; Clinical Trials, Phase II as Topic ; Colorectal Neoplasms/drug therapy ; Female ; Fluorouracil/therapeutic use ; Humans ; Male ; Middle Aged ; United States
    Chemical Substances Antimetabolites, Antineoplastic ; Antineoplastic Agents, Phytogenic ; irinotecan (7673326042) ; Fluorouracil (U3P01618RT) ; Camptothecin (XT3Z54Z28A)
    Language English
    Publishing date 1998-08
    Publishing country United States
    Document type Journal Article
    ZDB-ID 1067950-9
    ISSN 0890-9091
    ISSN 0890-9091
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  10. Article ; Online: Outcomes on anti-VEGFR-2/paclitaxel treatment after progression on immune checkpoint inhibition in patients with metastatic gastroesophageal adenocarcinoma.

    Kankeu Fonkoua, Lionel A / Chakrabarti, Sakti / Sonbol, Mohamad B / Kasi, Pashtoon M / Starr, Jason S / Liu, Alex J / Nevala, Wendy K / Maus, Rachel L / Bois, Melanie C / Pitot, Henry C / Chandrasekharan, Chandrikha / Ross, Helen J / Wu, Tsung-Teh / Graham, Rondell P / Villasboas, Jose C / Weiss, Matthias / Foster, Nathan R / Markovic, Svetomir N / Dong, Haidong /
    Yoon, Harry H

    International journal of cancer

    2021  Volume 149, Issue 2, Page(s) 378–386

    Abstract: Through our involvement in KEYNOTE-059, we unexpectedly observed durable responses in two patients with metastatic gastroesophageal adenocarcinoma (mGEA) who received ramucirumab (anti-VEGFR-2)/paclitaxel after immune checkpoint inhibition (ICI). To ... ...

    Abstract Through our involvement in KEYNOTE-059, we unexpectedly observed durable responses in two patients with metastatic gastroesophageal adenocarcinoma (mGEA) who received ramucirumab (anti-VEGFR-2)/paclitaxel after immune checkpoint inhibition (ICI). To assess the reproducibility of this observation, we piloted an approach to administer ramucirumab/paclitaxel after ICI in more patients, and explored changes in the immune microenvironment. Nineteen consecutive patients with mGEA received ICI followed by ramucirumab/paclitaxel. Most (95%) did not respond to ICI, yet after irRECIST-defined progression on ICI, all patients experienced tumor size reduction on ramucirumab/paclitaxel. The objective response rate (ORR) and progression-free survival (PFS) on ramucirumab/paclitaxel after ICI were higher than on the last chemotherapy before ICI in the same group of patients (ORR, 58.8% vs 11.8%; PFS 12.2 vs 3.0 months; respectively). Paired tumor biopsies examined by imaging mass cytometry showed a median 5.5-fold (range 4-121) lower frequency of immunosuppressive forkhead box P3+ regulatory T cells with relatively preserved CD8+ T cells, post-treatment versus pre-treatment (n = 5 pairs). We then compared the outcomes of these 19 patients with a separate group who received ramucirumab/paclitaxel without preceding ICI (n = 68). Median overall survival on ramucirumab/paclitaxel was longer with (vs without) immediately preceding ICI (14.8 vs 7.4 months) including after multivariate analysis, as was PFS. In our small clinical series, outcomes appeared improved on anti-VEGFR-2/paclitaxel treatment when preceded by ICI, in association with alterations in the immune microenvironment. However, further investigation is needed to determine the generalizability of these data. Prospective clinical trials to evaluate sequential treatment with ICI followed by anti-VEGF(R)/taxane are underway.
    MeSH term(s) Aged ; Antibodies, Monoclonal, Humanized/administration & dosage ; Antibodies, Monoclonal, Humanized/pharmacology ; Antineoplastic Combined Chemotherapy Protocols/administration & dosage ; Antineoplastic Combined Chemotherapy Protocols/pharmacology ; Disease Progression ; Gastrointestinal Neoplasms/drug therapy ; Gastrointestinal Neoplasms/pathology ; Humans ; Immune Checkpoint Inhibitors/administration & dosage ; Immune Checkpoint Inhibitors/pharmacology ; Male ; Middle Aged ; Neoplasm Metastasis ; Paclitaxel/administration & dosage ; Paclitaxel/pharmacology ; Pilot Projects ; Prospective Studies ; Survival Analysis ; T-Lymphocytes, Regulatory/drug effects ; T-Lymphocytes, Regulatory/metabolism ; Treatment Outcome ; Tumor Burden/drug effects ; Tumor Microenvironment/drug effects ; Ramucirumab
    Chemical Substances Antibodies, Monoclonal, Humanized ; Immune Checkpoint Inhibitors ; Paclitaxel (P88XT4IS4D)
    Language English
    Publishing date 2021-03-26
    Publishing country United States
    Document type Comparative Study ; Journal Article ; Research Support, N.I.H., Extramural
    ZDB-ID 218257-9
    ISSN 1097-0215 ; 0020-7136
    ISSN (online) 1097-0215
    ISSN 0020-7136
    DOI 10.1002/ijc.33559
    Database MEDical Literature Analysis and Retrieval System OnLINE

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