Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0019163 (hepatitis B)
 38,309 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The immune system has evolved under Darwinian pressures as a defence against ubiquitous viruses. Immune surveillance against viral antigens protects the normal host. Individuals with inherited or acquired immune-deficiency disorders can become vulnerable to ubiquitous viruses and neoplasms can ensue, such as B-cell lymphoma, hepatocellular carcinoma, squamous-cell carcinoma, Kaposi's sarcoma, and carcinoma of the penis and uterine cervix. Immunodeficiency permits Epstein-Barr virus, hepatitis B virus, papillomavirus, herpes simplex virus, and cytomegalovirus to induce sustained target-cell proliferation. Each virus selects specific cellular targets bearing viral receptors and the infection leads to proliferation of the target cells rather than lysis. Various co-factors, including nutrition, exposure to tumour-promoting agents, parasitic infection, and ultraviolet light, may promote carcinogenesis. Depending on the type and severity of the immune deficiency, gradual proliferation may lead to evolution of a malignant clone. Conversion of polyclonal virally infected proliferating cells to give monoclonal malignancy is probably due to specific cytogenetic rearrangements which allow oncogene activation and endow an altered tumour cell with selective growth advantages over normal diploid cells. Prevention of viral oncogenesis may be possible by treatment of immune-deficient individuals with premalignant disorders. Immunotherapy and antiviral therapy may prevent progression of viral-induced proliferation to malignancy. The purpose of this paper is to discuss and evaluate the role of immune deficiency and viruses in the induction of malignancies commonly occurring in Africans residing in sub-Saharan Africa (Purtilo, 1976). The types of malignancies commonly occurring in this region are believed to be due to ubiquitous viruses. A failure of immune surveillance mechanisms to recognize viral antigens and abrogate proliferation of infected target cells predisposes to malignancy by increasing the chance of a proliferating cell undergoing a cytogenetic or molecular alteration which endows it with malignant characteristics. The immunological surveillance hypothesis has been elaborated during this century by Ehrlich, Thomas, Burnet, and Schwartz (reviewed by Purtilo & Linder, 1983). This hypothesis rests on several assumptions: that neoplastic cells possess unique tumour antigens: tumour antigens provoke an immune response in the host; and the immune response is protective and eliminates the tumour.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Squamous-cell carcinoma, Kaposi's sarcoma and Burkitt's lymphoma are consequences of impaired immune surveillance of ubiquitous viruses in acquired immune deficiency syndrome, allograft recipients and tropical African patients. 610 Feb 88

The uses of GM-CSF as an immunomodulator and vaccine adjuvant are reviewed. GM-CSF has a variety of effects on immune responses: it induces class II major histocompatibility complex antigen expression on the surface of macrophages; it enhances dendritic cell maturation and migration; it results in a localized inflammation at the injection site; and it has marked effects on maturation of haematopoietic progenitor cells in the bone marrow. Animal and human studies suggest that administration of GM-CSF can increase antibody titres to foreign antigens. Monkeys injected with human interleukin (IL)-3 plus GM-CSF, at a different injection site, developed peak antibody titres which were 8- to 30-fold higher than those in monkeys injected with IL-3 alone. In a study of ovarian cancer patients receiving GM-CSF to prevent chemotherapy-induced neutropenia, two patients who had demonstrated a low titre of antithyroid antibodies prior to the study showed an increase in antibody titre and transient thyroiditis after administration of GM-CSF. Recently a GM-CSF/antigen fusion protein has been tested. An antibody corresponding to a specific idiotype expressed on B-cell lymphomas was fused to GM-CSF and injected into mice with B-cell lymphoma xenografts. The mice developed antibodies to the lymphoma and there was a protective effect against disease progression. Preliminary results of clinical trials using GM-CSF in humans suggest that it enhances antibody responses to hepatitis B vaccine. On the basis of these preliminary results, several clinical trials are being planned and it would appear that GM-CSF has potential as a vaccine adjuvant.
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PMID:Potential role of granulocyte-macrophage colony-stimulating factor as vaccine adjuvant. 787 53

Viruses implicated in the development of human cancers include hepatitis B (and C) viruses in hepatocellular carcinoma; human papillomaviruses in anogenital cancers; Epstein-Barr virus in nasopharyngeal carcinoma and Burkitt's lymphoma; human T-cell leukaemia/lymphoma viruses in adult T-cell leukaemia/lymphoma; and indirectly, human immunodeficiency viruses in Kaposi's sarcoma and B-cell lymphoma. Together, they contribute significantly to the cancer statistics in the Southeast Asian region. Neoplastic proliferation may be instigated by the presence and expression of viral oncogenes which may be integrated into the host genome and/or exist in episomal molecules. Critical viral genes may also interfere with host genes, resulting in the activation of cellular proto-oncogenes and/or the inactivation of anti-oncogenes and their products. The molecular pathogenesis of virally-induced cancers has led to major breakthroughs in the understanding of carcinogenesis at a molecular level. The occurrence of some of these viruses in a significant proportion of normal individuals suggests long latency periods necessitating multi-step co-operating events arising from multi-factorial agents such as host genetic susceptibility, immunological and hormonal status, as well as chemical and physical cocarcinogens in the environment. Successful intervention achieved with effective vaccines such as the hepatitis B vaccine and measures to severe the chain of viral transmission culminating in reduced incidence of the corresponding cancer will provide conclusive evidence for the virus-cancer relationship.
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PMID:Cancer and viruses. 810 16

A 49-year-old female with multiple endocrine neoplasia (MEN) type 1 associated with malignant lymphoma, lipoma, functioning adenomatous goiter, non-functioning adrenal tumor, polyneuropathy, postoperative primary hyperparathyroidism, and hepatitis B virus was a human T lymphotropic virus type 1 (HTLV-1) carrier. She underwent parathyroidectomy for primary hyperparathyroidism at age 44. At age 49, examinations of the enlarged para-aortic lymph nodes revealed diffuse small non-cleaved B cell lymphoma in stage II, and other various complications were also found. Multiple tumorigenetic factors were considered to be involved in the present case.
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PMID:Multiple endocrine neoplasia type 1 associated with malignant lymphoma and other complications. 896 95

It has been established that several types of cancers have a strong association with viruses. Thus, a potent antiviral compound without toxicity upon long-term usage will be useful not only for the treatment of viral diseases but also for the prevention or the delayed onset of those cancers that have a strong association with viruses. These compounds, depending upon their mechanism of action, could also potentially be useful for the treatment of those viral-associated cancers. L(-)Deoxynucleoside analogues were discovered in my laboratory and by others as an important class of antiviral and anti-cancer chemical entities. L(-)SddC (3TC, lamivudine), L(-)FTC, L(-)Fd4C, and L(-)FMAU are compounds with potent activity against hepatitis B virus (HBV), but with different biological and pharmacological profiles. These compounds may be useful in the prevention or delayed onset of hepatocellular carcinoma associated with HBV. L(-)I-OddU is a potent anti-Epstein-Barr virus (EBV) compound without cytotoxicity and animal toxicity upon long-term dosing, which allows drug concentration in plasma that are much higher than those that are antivirally active. This compound may have the potential to prevent B-cell lymphoma associated with patients undergoing organ transplants in addition to its potential use for the treatment of EBV infection. Furthermore, it may also be useful for the treatment of EBV-associated cancers. In this manuscript, the metabolism, mechanism of action and the resistance, as well as the potential use of this class of compounds targetted against HBV, will be discussed.
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PMID:L-Nucleoside analogues against cancer-causing viruses have potential in the prevention, delayed onset and treatment of viral associated cancers. 1159 88

In the Asia-Pacific region, autologous and allogeneic bone marrow transplantation (BMT) in patients infected with the hepatitis B virus (HBV) may be complicated by fatal hepatic failure due to viral reactivation. Survivors may suffer from accelerated hepatitis and cirrhosis. We report the first case of hepatocellular carcinoma (HCC) after autologous BMT for mediastinal B cell lymphoma. The tumor developed rampantly during a planned pregnancy 5 years after BMT. Less than 40 cases of HCC complicating pregnancy have been reported, and outcome is invariably poor. Immunosuppression and HBV reactivation after autologous BMT, as well as immune tolerance and hormonal changes associated with pregnancy may contribute to the rapid tumor growth. Biochemical and radiological surveillance for HCC should be strengthened in HBV carriers after BMT, especially in patients with the histology of chronic liver disease, or biochemical/ virological evidence of increased HBV activity.
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PMID:Aggressive hepatocellular carcinoma complicating pregnancy after autologous bone marrow transplantation for non-Hodgkin's lymphoma. 1185 Jul 14

Primary hepatic lymphoma (PHL) is a rare tumor and its clinical behavior remains unknown. We report a case of PHL in a 47 year-old male patient without chronic liver disease and with preoperative diagnosis of hepatocellular carcinoma. Hepatitis B surface antigen and antibody and anti-hepatitis C virus antibody were negative. The patient underwent a right trisegmentectomy, and pathologic examination revealed a diffuse large B-cell lymphoma. The clinical and pathologic features are presented. A review of the literature discussing clinical features, postulated pathogenetic mechanisms, and management options are also presented.
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PMID:[Primary non-Hodgkin's lymphoma of the liver. Report of a case and review of the literature]. 1206 31

A case of hepatitis B virus (HBV) reactivation after kidney transplantation is reported. The presence of antibodies against hepatitis B surface antigen (HBsAg) and hepatitis B core antigen (HBcAg) before transplantation indicated previous infection with HBV. Eight years after transplantation, a diffuse, large B-cell lymphoma occurred, and the patient was positive for HBsAg and hepatitis B e antigen, in association with normal activity of serum aminotransferases. Postmortem liver histology did not show any sign of portal tract or lobular inflammation despite the presence at immunostaining of extensive intranuclear and cytoplasmic positivity for HBcAg, indicating active viral replication. Natural immunity to HBV may not protect against reactivation in patients with a suppressed immune system. In this setting, periodic follow-up of HBV serology in patients at highest risk for HBV reactivation to allow for early diagnosis and prompt treatment with lamivudine is highly recommended.
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PMID:Hepatitis B virus reactivation after kidney transplantation and new onset lymphoma. 1259 Feb 43

A 51-year-old man without human immunodeficiency virus, hepatitis B virus or hepatitis C virus was admitted with left scrotum swelling and hydrocele. The cytological finding of fluid in the left scrotum revealed malignant lymphoma, and the immunophenotypic analysis and monoclonal rearrangement of immunoglobulin heavy chain demonstrated B-cell lymphoma. However, no solid tumor of lymphoma was identified in the specimen following a left orchiectomy, or in any other body site and genomic human herpes virus-8 and Epstein-Barr virus were not detected in the lymphoma cells. So we interpreted this as a primary effusion lymphoma without any ethological viral infection. Subsequently, he underwent chemo-radiation therapy and has remained in remission.
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PMID:Primary effusion lymphoma of the left scrotum. 1272 25

In the absence of prophylaxis, the reactivation of hepatitis B in oncology patients who are hepatitis B carriers is a well-known and often fatal complication of chemotherapy. The current recommendations in Canada and the USA are that patients who are positive for hepatitis B surface antigen (HBsAg) receive antiviral prophylaxis prior to chemotherapy. We report a 67-year-old man with B-cell lymphoma who developed hepatitis B reactivation following chemotherapy with cyclophosphamide, adriamycin, vincristine, prednisone and rituximab. Pre-chemotherapy, the patient was negative for HBsAg, positive for hepatitis B core antibody (anti-HBc) and weakly positive for hepatitis B surface antibody. Despite treatment with lamivudine, the patient died of fulminant hepatic failure. Our experience indicates that patients who are negative for HBsAg but positive for anti-HBc are still at risk for reactivation of latent hepatitis B during and after chemotherapy and may be considered for prophylaxis.
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PMID:Fatal reactivation of hepatitis B post-chemotherapy for lymphoma in a hepatitis B surface antigen-negative, hepatitis B core antibody-positive patient: potential implications for future prophylaxis recommendations. 1601 63


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