Parathyroid Hormone-Related Protein in Hypercalcemia Associated with Hematological Malignancy

Hypercalcemia is an important complication in multiple myeloma as well as T-cell leukemia/lymphoma, and is moderately common in high and intermediate grade non-Hodgkin's lymphoma. The underlying mechanism has been unclear because the neoplastic cells are usually present in the bone marrow, where they are in a position to produce short range effects on bone resorption which are difficult to identify. This contrasts with the situation in hypercalcemia associated with non-metastatic carcinoma, where it has been clearly demonstrated that the most common cause is release from the tumor of a humoral mediator, Parathyroid Hormone-related Protein (PTHrP). Roles have been advocated in multiple myeloma for release of a number of other cytokines with osteolytic capacity on the basis of their enhancement of osteolytic activity in cultured fetal rat bone, although a causal relationship in patients has not been established. PTHrP has more recently been implicated in the genesis of hypercalcemia in patients with hematological malignancies by the demonstration in a proportion of cases of increased circulating levels of PTHrP, comparable to those in hypercalcemia due to cancer. Immunohistochemical studies indicate neoplastic hemopoietic cells can contain PTHrP, and thus have the capacity to act in a paracrine manner to enhance local bone resorption and contribute to the development of hypercalcemia.     

Serum Soluble Interleukin-2 Receptor Levels in Patients with Adult T-cell Leukemia and Human T-cell Leukemia/Lymphoma Virus Type-I Seropositive Healthy Carriers

Using an enzyme-linked immunosorbent assay (ELISA) technique, we measured the soluble interleukin 2 receptor (s-IL-2R) levels in the sera of patients with adult T-cell leukemia (ATL) in Japan. The s-IL-2R levels in the sera of the ATL patients were markedly higher (range 540-310, 400 U/ml, mean ±SD=62,800 ±81,000 U/ml, n = 42) than those in normal individuals (range 42-950 U/ml, mean ±SD=322 ±198 U/ml, n = 35, P<0.01). The patients with acute-type or lymnhoma-type ATL had high s-IL-2R levels (range 11,900-310,400 U/ml, mean ±SD= 110,340 ± 370 U/ml, n = 15; range 26,400-214,400 U/ml, mean ±SD=90,170 ±59,040 U/ml, n = 7, respectively). All of the patients with hypercalcemia (Ca>10 mg/dl) or elevated serum LDH levels (LDH > 500 IU/liter) also had s-IL-2R levels above 10,000 U/ml. The high s-IL-2R levels in the sera of ATL patients indicate abnormal IL-2 receptor production and its release from the leukemic cells in vivo . Thus, the serum s-IL-2R level may be a sensitive and useful marker to monitor the total amount of tumor cells in ATL, especially in the lymphoma type. We next examined the serum s-IL-2R levels in human T-cell leukemia/lymphoma virus type-I (HTLV-I) seropositive healthy carriers to investigate whether there might he abnormal IL-2 receptor expression in such individuals. However, there was no statistically significant difference between the S-IL-2R level of 71 HTLV-I seropositive healthy carriers (range 65-880 U/ml, mean±SD =394±212 U/ml) and that of 71 age- and sex-matched normal individuals (range 33-950 U/ml, mean ±SD=357 ±224 U/ml) who lived in Okinawa Prefecture.     

Lymphomatous Presentation of CD4+/CD8+ HTLV-1-Related Adult T-cell Leukemia/Lymphoma in an Iranian Woman

Adult T-cell leukemia/lymphoma (ATLL) remains an uncommon disorder outside well-defined risk groups. We describe the case of an Iranian woman, who presented with isolated meningeal relapse of diffuse large-cell lymphoma. The malignant cells coexpressed CD4 and CD8 and HTLV-1 seropositivity was confirmed. Despite combination chemotherapy disseminated lymphoma developed. Preterminally the characteristic features of ATLL were noted; hypercalcemia, with normal parathyroid hormone-related protein and vitamin D levels, and peripheral blood leukemic involvement.     

Isolation of Virus-producing Transformants from Human Gastric Cancer Cell Line, HGC-27, Infected with Human T-cell Leukemia Virus Type I

A human anaplastic gastric cancer cell line, HGC-27, showed marked degeneration with formation of multinucleated syncytia and cell detachment of nearly all cells which began 24 hr after and reached a maximum 2 to 3 days after co-cultivation with X-irradiated MT-2 cells, HTLV-I producing human cord leukocytes. Less severe degeneration without formation of syncytia was also observed in the cultures inoculated with cell-free MT-2 culture media. Morphologically altered cells began to proliferate and formed piled up colonies in some of the cultures co-cultivated with X-irradiated MT-2 cells after a long culture period. The two clones designated HGC/MT2 (Cl-1) and HGC/MT2 (Cl-2) were separated by cell cloning. HGC/MT2 (Cl-1) and HGC/MT2 (Cl-2) cells were positive for HTLV-I gag proteins (p19 and p24) and pX gene products, p40^x, as demonstrated by immunohistochemistry and immunoblotting analysis, contained HTLV-I provirus DNA, and consistently produced type C virus particles.     

Dysgerminoma of the Ovary with Hypercalcemia Associated with Elevated Parathyroid Hormone-related Protein

The purpose of the present paper is to present a rare case ofdysgerminoma of the ovary with hypercalcemia showing elevationof multiple serum tumor markers including parathyroid hormone-relatedprotein (PTH-rP). An 18-year-old unmarried woman, with ovariandysgerminoma showing hypercalcemia and elevated serum PTH-rP,received six courses of a combination chemotherapy consistingof bleomycin, etoposide and cisplatin after her first surgery,and had no evidence of recurrence approximately 30 months aftercompleting the chemotherapy.     

The Differences between Lymphoma and Leukemia Type of Adult T-cell Leukemia

The difference between lymphoma type and leukemia type of adult T-cell leukemia (ATL) were analysed with 102 Japanese patients all positive for human T-cell leukemia virus type I (HTLV-I) antibody. They were classified into three groups on findings at first medical examination: lymphoma type cases, leukemia type cases, and mixed type (leukemia type plus lymphadeno-pathy) cases. Lymphoma type patients had several or more enlarged lymph nodes the largest of which was greater than 1 cm in diameter and with practically no abnormal lymphocytes (ATL. cells), which are characteristic of ATL, in the peripheral blood. Leukemia type patients had 10% or more ATL cells in the peripheral blood and had no detectablle lymphadenopathy Lymphoma type patients often complained of detectable lymphadenopathy, while leukemia type patients complained frequently of general fatigue and skin eruption. Mixed type patients more frequently had signs and symptoms which were characteristic of both types: lymphadenopathy and 10% or more ATL cells in the peripheral blood. Mixed type: ATL had a poorer prognosis than either lymphoma type or leukemia type. The median survival time was 3 months for mixed type patients, 10.5 months for lymphoma type patients, and 13.5 months for leukemia type patients. Complications and causes of death have also been touched upon. Clinicians are thus advised to consider ATL patients separately according to their clinical manifestations.     

Effects of Glucocorticoids and Calcitonin on Parathyroid Hormone-related Protein (PTHrP) Gene Expression and PTHrP Release in Human Cancer Cells Causing Humoral Hypercalcemia1

Glucocorticoids are widely used for the treatment of malignancy-associated hypercalcemia to delay the occurrence of an escape phenomenon inherent in calcitonin therapy. Using parathyroid hormone-related protein (PTHrP)-producing squamous carcinoma cells (T3M-1 and EC-GI) established in our laboratory, we investigated the in vitro effects of glucocorticoids and calcitonin on PTHrP mRNA expression in the cells and release of PTHrP into the culture medium. The PTHrP gene was constitutively expressed in the logarithmic growth phase in both squamous carcinoma cell lines. When these cells became superconfluent, PTHrP mRNA expression was greatly diminished in T3M-1 cells but was not distinctly diminished in EC-GI cells. Hydrocortisone inhibited the PTHrP mRNA expression in T3M-1 cells and EC-GI cells in a dose-dependent manner. In accordance with the decreased expression of PTHrP mRNA, the release of immunoreactive as well as bioactive PTHrP also decreased in the conditioned medium of glucocorticoid-treated cells. The minimal effective concentration of prednisolone was about 10 -7 M, which is readily attainable in the serum of patients treated with the agent. Calcitonin and indotnethacin did not affect the PTHrP mRNA expression or PTHrP release into the medium. Calcitonin did not modulate the hydrocortisone-induced inhibition of PTHrP production. These in vitro findings suggest that the combined use of glucocorticoids and calcitonin plays a beneficial role in the treatment of malignancy-associated hypercalcemia, since the steroid hormone can suppress PTHrP mRNA expression and release of bioactive PTHrP in certain PTHrP-producing tumors.     

Unusual Morphological Features of Adult T-cell Leukemia Cells with Aberrant Immunophenotype

We describe 4 cases of adult T-cell leukemia (ATL) with unusual morphology and aberrant immunophenotype. All patients were Japanese and born in the Nagasaki district, an area endemic for HTLV-I. Peripheral blood and/or bone marrow films revealed bizarre giant cells with and without large nucleoli; the cells were 5 to 6 times the diameter of erythrocytes, resembling Hodgkin's cells. Some peripheral blood cells were morphologically similar to prototypic ATL cells, while many other cells in the bone marrow showed unusual morphology. Furthermore, leukemic cells had aberrant immunophenotypes such as the CD8-positive type in patients 1 and 2, the CD4^- ˙ CD8^- double-negative type in patient 3, and the CD5 antigen defect in patient 4. All patients had marked elevations of the serum calcium and LDH and organomegaly, while all had a short survival. Anti-HTLV-I antibodies and provirus DNA monoclonality were demonstrated in all patients.

The results suggested that the unusual morphology and aberrant ATL cell immunophenotype may be indicative of a high grade malignant behaviour of ATL.     

Enhancing Effect of Interleukin-2 on Production of Parathyroid Hormone-related Protein by Adult T-Cell Leukemia Cells

Leukemic cells from patients with adult T-cell leukemia (ATL) can produce a calcium-regulating protein, parathyroid hormone-related protein (PTHrP). Moreover, it has been reported that ATL cells produce some cytokines besides PTHrP and that these cells respond to the T-cell growth factors, interleukin-2 (IL-2) and interIenkin-4 (IL-4). To elucidate whether PTHrP produced by ATL cells is regulated by IL-2 or IL-4, we investigated the in vitro effects of IL-2 and IL-4 on the release of PTHrP. IL-2 increased the release of PTHrP into the conditioned medium from leukemic cells in some, but not all, ATL patients; however, IL-4 did not affect the PTHrP release. PTHrP messenger RNA (mRNA) levels were increased in ATL cells cultured in the presence of IL-2. These data suggest that IL-2 plays a role in the regulation of hypercalcemia by enhancing the production of PTHrP in ATL patients.     

Circulating Parathyroid Hormone-related Protein (109-141) in Malignancy-associated Hypercalcemia

For differential diagnosis between hypercalcemia-induced bonemetastasis and humoral hypercalcemia of malignancy (HHM), serumparathyroid hormone-related protein (PTHrP) concentrations weremeasured in normal subjects and patients with malignancy-associatedhypercalcemia according to the presence or absence of bone metastasis,using a new sensitive PTHrP(109–141) radioimmunoassaysystem. The serum PTHrP(109–141) levels in all of 14 patientswithout bone metastasis were significantly higher than thosein normal subjects. However, in four patients with hypercalcemiaassociated with bone metastasis the levels were nearly the sameas those in normal subjects. The time course in two hypercalcemicpatients with esophageal carcinoma revealed that serum PTHrP(109–141)levels were elevated before hypercalcemia developed and thatchanges in PTHrP(109–141) and corrected serum calciumlevels were significantly correlated. These findings suggestthat determination of serum PTHrP(109–141) may be clinicallyimportant not only for differential diagnosis of HHM but alsoas a useful predictive marker of hypercalcemia.     

Urinary excretion of parathyroid hormone-related protein as a predictor of hypercalcemia in patients with adult T-cell leukemia.

Hypercalcemia with adult T-cell leukemia (ATL) is chiefly caused by an excessive production by tumor cells of parathyroid hormone-related protein (PTHrP). We have previously reported hypercalcemic patients with solid tumors to excrete a large amount of the C-terminal fragments of PTHrP (C-PTHrP) into their urine. To elucidate whether PTHrP production correlates with or predicts the development of hypercalcemia, we studied the urinary excretion of C-PTHrP in 36 ATL patients. The urinary excretion of C-PTHrP was in the normal range (< 0.40 nmol equivalent to PTHrP (109-141)/g creatinine) in HTLV-1-positive carriers (n 3), ATL patients in complete remission (n 2) and chronic type ATL patients (n 2). It was marginally increased in seven patients in partial remission, and gradually increased as the disease progressed. In 20 patients who died without or with hypercalcemia, it was increased to 1.98 +/- 0.69 (n 9) and 7.6 +/- 2.1 nmol/g creatinine (mean +/- SD, n 11, P < 0.01), respectively. Urinary C-PTHrP excretion was significantly correlated with serum calcium and LDH levels as well as with CD25-positive cells in the peripheral blood. In four patients whose urinary excretion had been serially determined, it increased prior to the development of hypercalcemia. The findings suggest the urinary excretion of C-PTHrP to be of use as a predictor of the development of hypercalcemia in ATL patients. In ATL patients whose urinary excretion of C-PTHrP is progressively increasing, the serum calcium concentration should be carefully monitored to prevent hypercalcemic crisis.     

Clinicopathological Features of Adult T-Cell Leukemia with CD30 Antigen Expression

Recently, several cases of adult T-cell leukemia (ATL) with CD30 antigen have been reported, but its clinical significance remains unknown. Accordingly, we studied CD30 antigen expression in ATL cases and documented the clinicopathological characteristics of these cases.

Immunohistochemical and clinical characteristics were studied in 46 patients with malignant lymphoma or benign lesions of lymphoid tissue, who had antibodies against human T-cell leukemia virus type I (HTLV-I). Monoclonal integration of HTLV-I provirus was demonstrated in the tumor cells in 36 (ATL) of the 46 cases. CD30 antigen expression was evident in seven of these 36 cases (19.4%), however it was not seen in any of the ten cases lacking the integration of HTLV-I provirus. A comparison of ATL cases with and without CD30 antigen expression revealed significantly larger numbers of abnormal lymphocytes in the peripheral blood and lower serum calcium levels in ATL expressing CD30 antigen.     

Comparison of CHOP versus VEPA Therapy in Patients with Lymphoma Type of Adult T-cell Leukemia

Forty-six Japanese patients with lymphoma type of adult T-cell leukemia (ATL) were treated with one of the 4-drug combinations, CHOP or VEPA regimen. Fourteen patients were treated with CHOP, while 32 were treated with VEPA. The complete response i(CR) rate and the 5-year survival rate of patients treated with CHOP were 35.7% and 7.1%, respectively, while for those treated with VEPA the rates were 43.8% and 18.7%, respectively. Only two patients treated with CHOP survived for more than 1 year, while the others died within 1 year. On the other hand, 13 patients treated with VEPA survived for more than 1 year. The 32 VEF'A-treated patients were divided into two groups according to the duration of survival: (A) 13 surviving for more than 1 year, and (B) 19 surviving for less than 1 year. They were compared for pretreatment characteristics. The differences between the two groups related to hepatomegaly, the presence of B symptoms, lactic dehydrogenase (LDH) and calcium levels. The results indicate that these factors are important in predicting the response and survival of patients with lymphoma type of ATL.     

甲状旁腺素相关肽与肿瘤

甲状旁腺素相关肽(PTHrP)参与调节钙磷代谢和多器官的生长发育,在恶性肿瘤发生骨转移和高钙血症过程中发挥重要作用.越来越多的研究证实PTHrP可以由多种类型的肿瘤细胞分泌,参与调节肿瘤细胞的增殖、侵袭,并与患者预后密切相关,为肿瘤治疗提供了新的靶点.     

Plasma Soluble CD30 as a Possible Marker of Adult T-cell Leukemia in HTLV-1 Carriers: a Nested Case-Control Study

Elevated levels of soluble CD30 (sCD30) are linked with various T-cell neoplasms. However, the relationship between sCD30 levels and the development of adult T-cell leukemia (ATL) in human T-cell leukemia virus type 1 (HTLV-1) carriers remains to be clarified. We here investigated whether plasma sCD30 is associated with risk of ATL in a nested case-control study within a cohort of HTLV-1 carriers. We compared sCD30 levels between 11 cases (i.e., HTLV-1 carriers who later progressed to ATL) and 22 age-, sex- and institution-matched control HTLV-1 carriers (i.e., those with no progression). The sCD30 concentration at baseline was significantly higher in cases than in controls (median 65.8, range 27.2-134.5 U/mL vs. median 22.2, range 8.4-63.1 U/mL, P=0.001). In the univariate logistic regression analysis, a higher sCD30 (≥30.2 U/mL) was significantly associated with ATL development (odds ratio 7.88 and the 95% confidence intervals 1.35–45.8, P = 0.02). Among cases, sCD30 concentration tended to increase at the time of diagnosis of aggressive-type ATL, but the concentration was stable in those developing the smoldering-type. This suggests that sCD30 may serve as a predictive marker for the onset of aggressive-type ATL in HTLV-1 carriers.     

Cell-free Entry of Human T-Cell Leukemia Virus Type 1 to Mouse Cells

Human T-cell leukemia virus type 1 (HTLV-1) is the etiologic agent for adult T-cell leukemia and HTLV-1-associated myelopathy/tropical spastic paraparesis. Recently we infected newborn mice by inoculating HTLV-1-producing human cells, and found that T-cells, B-cells and granulocytes were infected in vivo. To understand the mechanism of viral-cell interaction and the pathogenesis of HTLV-1 using the mouse model, it is important to clarify the cellular tropism using a cell-free HTLV-1 transmission system. We employed a highly transmissible cell-free HTLV-1 produced by a feline kidney cell line, c77, and studied the susceptibility of 9 kinds of mouse cell lines, EL4, RLml, CTLL-2, J774.1, DA-1, Ba/F3, WEHI-3, NIH3T3 and Bl, and two kinds of human cell lines, Molt-4 and Hut78. HTLV-1 proviral sequence was found by PCR in all 9 mouse cell lines as well as in 2 human cell lines and viral entry was blocked with sera from an HTLV-1 carrier and an adult T-cell leukemia patient. Unexpectedly, mouse cell lines EL4 and RLml and human cell lines Molt-4 and Hut78 showed similar efficiency for viral entry. These results suggest a wide distribution of HTLV-1 receptor in mouse cells.     

Electron Microscopic Study of Cell Lines Established from Adult T-Cell Leukemia--Coexistence of Adult T-Cell Leukemia Virus and Epstein-Barr Virus

Six cell lines established from five patients with adult T-cellleukemia (ATL) were studied by electron microscopy. From onepatient two cell lines were established, an interleukin 2-dependentline and a nondependent line. The interleukin 2-dependent T-cellline had only ATL virus (ATLV) particles. The interleukin 2-nondependentB-cell line had both ATLV particles and Epstein-Barr virus (EBV)particles. In two other B-cell lines and one undetermined cellline, both ATLV particles and EBV particies were seen. In oneB-cell line only a few EBV particles were seen. These findingssuggest that (I) interleukin 2 is necessary for the growth ofleukemic T-cells from ATL tissue samples, and (2) ATLV can infectnot only T-cells but also B-cells.     

IgG-κ-Type Plasmacytoma Secreting Salivary-Type Amylase in Adult T-Cell Leukemia

A IgG-κ-type plasmacytoma secreting salivary-type amylase ectopically is reported in a patient with smouldering adult T-cell leukemia(ATL). The patient had plasmacytomas in the distal region of the right femur, the proximal region of left tibia, and the left paranasal sinus. Both his serum and urine contained high levels of amylase. The presence of IgG-κ and S-type amylase in the plasmacytoma cells was confirmed immunocytochemically. In addition, he was also positive for the antibody against the human T-cell leukemia virus type I (HTLV-I), and had abnormal lymphocytes with convoluted nuclei(ATL cells) in the peripheral blood. The monoclonal integration of HTLV-I proviral DNA was demonstrated in the leukemic cells of the peripheral blood, but not in the plasmacytoma cells. Our case suggested that not only can HTLV-I infection play a role in the development of ATL, but may also induce a B-cell malignancy in an indirect manner, and even an ectopic amylase producing plasmacytoma.