Monocyte maturation and prognosis in primary breast cancer

ERK activity facilitates activation of the S-phase DNA damage checkpoint by modulating ATR function

Although Erk kinase has been recently reported to function in the DNA damage response, the mechanism governing this process is unknown. We report here that hydroxyurea (HU) activates Erk via MEK1, a process that is sensitized by a constitutively active MEK1 (MEK1Q56P) and attenuated by a dominant-negative MEK1 (MEK1K97M). While ectopic MEK1Q56P sensitized HU-induced S-phase arrest, inhibition of Erk activation via U0126, PD98059, and MEK1K97M attenuated the arrest, and thereby enhanced cells to HU-induced toxicity. Taken together, we demonstrate an important contribution of Erk to the activation of the S-phase DNA damage checkpoint. This can be attributed to Erk's regulatory role in modulating ATR function. Inhibition of Erk activation with U0126/PD98059 and MEK1K97M substantially reduced HU-induced ATR nuclear foci, leading to a dramatic reduction of gammaH2AX and its nuclear foci. Reduction of MEK1 function by a small interference RNA (siRNA) MEK1 and ectopic MEK1K97M significantly decreased HU-induced gammaH2AX. Conversely, ectopic MEK1Q56P enhanced gammaH2AX foci. Furthermore, immunofluorescent and cell fractioning experiments revealed cytosolic and nuclear localization of ATR. HU treatment caused the redistribution of ATR from the cytosol to the nucleus, a process that is inhibited by U0126. Collectively, we show that Erk kinase modulates HU-initiated DNA damage response by regulating ATR function.

Effects of doxorubicin on maturation of human monocytes in adherent and non-adherent cultures

Purified human monocytes were cultured for 2 h, 88 h, and 10 days in plastic tubes (adherent) and for 10 days in Teflon foil bags (non-adherent). Monocytes were incubated with doxorubicin by two short-term exposures (750 or 1500 ng/ml) for 1 h or by continuous exposure (75 ng/ml). Maturation was monitored by measuring the intracellular activity of three metabolic enzymes and two acid hydrolases. Expression of receptors for the Fc moiety of immunoglobulin G (FcRI, FcRII, FcRIII), CD14, and HLA-DR was assayed by indirect immunofluorescence with monoclonal antibodies. In the presence of doxorubicin, the adherent capacity, the yield, and the enzyme activities reflecting growth and intermediary metabolism were similar to the control groups. However, doxorubicin reduced the expression of FcRI (32-45%), FcRII (10-26%), CD14 (20-37%), and HLA-DR (25-34%) on the monocyte-derived macrophages. Expression of FcRIII was not detectable after 10 days of culture.

Effects of cimetidine on in vitro transformation of peripheral monocytes to macrophages in healthy volunteers and cancer patients

Monocyte-to-macrophage transformation is a phenomenon which correlates with the absolute number of mononuclear cells, principally lymphocytes, contained in the culture. The addition of cimetidine to cultures of mononuclear cells from the peripheral blood of healthy volunteers enhances monocyte transformation (probably by way of blocking the H2 receptors of suppressors T lymphocytes) regardless of the absolute number of monocytes in the culture or of basal transformation rates. Removal of the lymphocytes from the cultures lowers the basal transformation rate and prevents the effect of cimetidine. The addition of histamine to the cultures causes significant depression of the monocyte transformation rate; this effect is partly offset by the concurrent addition of cimetidine. In the case of cancer patients, mononuclear cell cultures from peripheral blood fail to respond to cimetidine even though basal transformation rates are not significantly different from those of healthy controls; this suggests some intrinsic impairment of monocyte function, possibly mediated by blocking factors produced by the tumor.

Monocyte function in cervical carcinoma: plasma inhibitor of monocyte chemotaxis

Blood monocyte function was tested in 43 untreated patients with carcinoma of the cervix (stages Ib to IIIb) and 50 age-matched controls. Monocyte counts, adhesion to glass, spreading on glass, phagocytosis and killing of Candida albicans, and chemotaxis under agarose were not significantly different between the patient and control groups. In 65% of a further series of 17 patient/control pairs, the plasma of cervical carcinoma patients was shown to contain a cell-directed inhibitor of monocyte chemotaxis. The accumulated evidence indicates that production of such factors by malignant tumors is an important mechanism in counteracting mononuclear phagocyte defense.

Mononuclear phagocyte function in head and neck cancer. Chemotactic responsiveness of blood monocytes in correlation between histologic grade of the tumor and infiltration of these cells into the tumor area

The chemotactic responsiveness of peripheral monocytes and the acid-phosphatase activity of tumor-infiltrating macrophages, as well as the ultrastructural appearance, were studied in 40 patients with squamous cell carcinoma of the head and neck. The chemotactic responsiveness was found to be decreased in carcinoma patients, and this value appeared to be positively correlated in individual patients with the number of tumor-infiltrating macrophages, as well as with the histologic grade of the tumor. Patients with poorly differentiated malignancies showed impaired monocyte chemotactic responsiveness and low numbers of tumor-infiltrating macrophages. Macrophages present in the parenchyma of the tumor showed a weak and diffuse pattern of acid phosphatase activity. The acid phosphatase activity of stromal macrophages was much stronger and distributed in foci. Electron microscopic examination of the parenchymal macrophages revealed low numbers of lysosomes and the presence of tumor cell debris in the cytoplasm of the cell, without any sign of a surrounding phagosomal membrane. Together with the weak cytochemical reactivity, this probably indicates the poor functional state of the phagocyte when infiltrated in the parenchyma of the tumor. Low molecular weight factors derived from the tumor are known to decrease chemotactic responsiveness of peripheral monocytes. The poor functional state of the macrophages infiltrated within tumor parenchyma might be explained by assuming that a high concentration of such factors in the near vicinity of malignant cells causes toxic effects in macrophages.

Receptor associated defects of cultured monocytes in bronchial carcinoma

Using peripheral blood monocytes from individuals with bronchial carcinoma (BC) we have measured changes, over an 8 day culture period, in monocyte/macrophage complement (C3b) and IgG (Fc) rosettes, chemotactic factor (CF)-induced enhancement of C3b and IgG (Fc) rosettes, and the phagocytic index (PI) for yeast particles. The same measurements were made on monocyte/macrophages from individuals with non-malignant respiratory diseases (NMRD) and healthy controls (HC). Following 8 days of culture there was a significant increase in C3b rosettes, IgG (Fc) rosettes and the PI in NMRD and HC. In contrast there was no significant increase in C3b rosettes in BC. The PI increased in BC, but on day 8 was still significantly less than control monocytes/macrophages. IgG (Fc) rosettes increased in BC following culture to a similar degree as that observed with NMRD and HC. In addition, there were no differences between BC and HC in CF-induced enhancement of IgG (Fc) rosettes at either day 0 or day 8 of culture whereas complement receptor enhancement in BC was impaired both at the beginning and end of the 8 day culture period. These results indicate that in advanced BC there is an abnormality in the expression of monocyte/macrophage complement receptors (which is not readily demonstrable for IgG [Fc]receptors) and that the defect persists following an 8 day culture period.

Characterization of monocyte maturation in adherent and suspension cultures and its application to study monocyte differentiation in Hodgkin's disease

Monocytes purified with cell scatter monitored counterflow centrifugation were cultured in plastic (adherent) and in teflon culture bags (suspension). Sequential changes were monitored during 15 days by measuring intracellular activity of three enzymes of intermediary metabolism: glucose-6-phosphate dehydrogenase (G-6-PDH), phosphohexose isomerase (PHI) and isocitrate dehydrogenase (ICDH), and the two acid hydrolases: acid phosphatase (ACP) and N-acetyl-beta-glucosaminidase (NAG). In teflon grown macrophages a significantly lower G-6-PDH activity was seen after 15 days in comparison to plastic adherent macrophages (P less than 0.0002). For the other enzymes similar values for both culture modalities were found. The significantly, cycloheximide insensitive, higher values for G-6-PDH, PHI and ICDH in 2 h plastic adherent monocytes in comparison with plastic non-adherent monocytes, suggest a relationship between adherent capacity and the level of intermediary metabolism. The overall yield of plastic adherent macrophages after 15 days was 35% in contrast with 89% for the in suspension cultured macrophages. This corroborates the existence of adherent and non-adherent monocytes, both capable of differentiation in vitro. In 14 patients with advanced Hodgkin's disease (HD) and 14 normal controls, monocyte differentiation was studied applying both culture modalities. The enzyme levels, reflecting growth and intermediary metabolism, were similar for both groups. The adherent capacity and yield, both in teflon and in plastic, after 15 days was comparable for both groups. It was concluded that in vitro monocyte differentiation in the presence of autologous serum was qualitatively and quantitatively normal in advanced HD; this is in favour of an intrinsically normal function of monocytes in HD.

Culture of peripheral monocytes in vitro in patients with renal cell carcinoma: a possible prognostic indicator

An in vitro assay has been applied in 23 patients with renal cell carcinoma. A mononuclear cell-rich fraction was cultured from peripheral blood of patients with renal cell carcinoma. The number of monocytes maturing into macrophages was quantitated over a period of 7 days. Monocyte maturation was significantly lower in patients with renal cell carcinoma than in normal individuals. Of 10 patients tested both pre- and post-nephrectomy, 8 patients showed clinical improvement after surgery. In all 8, the posttreatment macrophage yield improved significantly from the pretreatment values to approach normal values. In 2 patients found to have metastasis postoperatively, the macrophage yield continued below normal levels. Our results suggest that the in vitro maturation of macrophages from mononuclear cells may parallel clinical events.

Ultrastructure of skin window cells in normal subjects

Ultrastructural studies have been made of skin window inflammatory cells in 22 healthy human subjects at 24 hours and 48 hours after an initial abrasion. Large numbers of macrophages and neutrophil polymorphs were seen at both intervals. Compared with the 24 hours specimens, macrophages at 48 hours tended to have more eccentric and less irregular nuclei, as well as more voluminous cytoplasm; phagosomes and large vacuoles were much more prominent and cell diameters were larger. The differences are consistent with maturational changes in the macrophages during the inflammatory response. In the neutrophil polymorphs, the nuclei were frequently pycnotic and showed multiple profiles, and the complement of granules was small. Other cell types were only occasionally encountered. It is concluded that ultrastructural studies of skin window cells may have an application in investigating maturational defects of macrophages in malignant states.

In vitro monocyte maturation in squamous-cell carcinoma of the lung: influence of humoral factors

A previously described defect of in vitro monocyte maturation in patients with squamous-cell carcinoma of the lung (SCC) has been investigated further. The maturation of patients' monocytes in pooled normal human serum was significantly better than in autologous serum. Conversely, the maturation of normal control monocytes was significantly depressed in patients' serum. The defect has been shown to be due to the presence of an inhibitory factor, rather than the lack of a necessary component in the patients' serum. Artificially aggregated gamma-globulin inhibited monocyte maturation in vitro, but the presence of immune complexes in the serum of many patients with SCC did not correlate well with the depression of in vitro maturation of monocytes from the same patient. Similarly, pregnancy-associated alpha 2-glycoprotein, in increased amounts in the serum of patients with SCC, showed no correlation with monocyte maturation. The addition of soluble extracts of tumour, but not of surrounding normal lung tissue significantly inhibited monocyte maturation. The results suggest that the defective monocyte maturation in patients with SCC is at least in part due to serum inhibitory factors, which are likely to be a heterogeneous group.

Fc receptor-bearing peripheral blood mononuclear cells in breast cancer patients: a possible marker of tumour burden and prognosis

Indirect immunofluorescence was used to identify and quantitate peripheral blood mononuclear (PBM) cells possessing high avidity Fc receptors in 105 patients upon referral to the breast cancer clinic at the Cross Cancer Institute. The cell detected was shown to be a non-adherent PBM, probably belonging to the T or null cell population. The mean percentage +/- 2 standard deviations of PBM-positive cells in 75 patients with no disease or benign breast disease was 5.3 +/- ;6.7, and this was significantly (P less than 0.001) less than the percentage found for 31 patients with breast cancer. The percentage of PBM-positive cells correlated directly with tumour burden in patient with small (less than or equal to 5 cm) tumours without regional node or extranodal metastases (5/13 had greater than or equal to 12% positive PBM) and in those with small tumours plus regional node metastases, but without extranodal metastases (8/10 had greater than or equal to 12% positive PBM). This correlation was less, however, in patients with large tumours (greater than 5 cm), and in those with extranodal metastases (4/8 had greater than or equal to 12% positive PBM), and in patients tested postoperatively (1/13 had greater than or equal to 12% positive PBM) even though 6!13 had regional node metastases at the time of surgery. Thus, this relatively simple assay, which can be done on peripheral blood samples, may turn out to be useful in patients with breast cancer as a prognostic marker insofar as it may be an indirect indicator of tumour burden preoperatively. If so, it may lead to a more aggressive postoperative adjuvant therapy approach to the subpopulation of node-negative PBM-positive breast cancer patients than is currently used for node-negative patients.

In vitro monocyte maturation as a prediction of survival in squamous cell carcinoma of the lung

In vitro monocyte maturation was studied in patients with squamous cell carcinoma of the lung--limited to the ipsilateral hemithorax in 30 and more extensive in 40. The patients were studied prospectively and initial monocyte maturation was correlated with survival. Monocyte maturation in patients with limited disease before treatment ranged from 3.1 to 57.6% with a median value of 21.4%. The survival of those patients in whom monocyte maturation was less than the normal range (less than 30.4%) was significantly shorter than the survival in those with normal maturation ( p less than 0.05). Four of the five patients whose initial maturation was less than 10% proved to be inoperable at surgery. Patients with extensive disease had monocyte maturation ranging from 2.4 to 52.9% with a median value of 13.2%, significantly lower than in those with limited disease (p less than 0.025). Patients with extensive disease and low monocyte maturation survived a significantly shorter time than those with normal maturation ( p less than 0.005). The depression of monocyte development may explain the finding of negative delayed hypersensitivity skin reactions in many patients with lung carcinoma and may prove useful as an index of prognosis.

In vitro monocyte maturation in squamous carcinoma of the lung

Maturation of monocytes into macrophages in vitro has been assayed by a quantitative microtitre assay in patients with squamous-cell carcinoma of the lung. Monocyte maturation in autologous serum was significantly depressed in patients with both limited and extensive disease compared with normal controls, patients with chronic obstructive airways disease and controls matched for age, sex, smoking history, respiratory function and the presence of infection. Maturation of monocytes from patients with terminal non-malignant disease was depressed, though not to the same extent as in those with extensive malignancy. Monocytes from relatives of patients with squamous-cell carcinoma of the lung matured normally. In 10 patients with limited disease, in vitro monocyte maturation was repeated 6-12 weeks after operation, and was found to relate to prognosis.

The search for occult metastases in breast cancer: does it add to established staging methods?

In 1974 a project was initiated in which patients with apparently operable breast carcinoma underwent special investigations in an attempt to identify occult metastasis in bone and liver. One hundred and seventy-two patients have been followed for two years or more and their axillary node histological findings reviewed. From analysis of these patients the following conclusions may be drawn. Careful clinical assessment, especially measurement of the primary tumour and palpation of the axillary nodes, remains a fundamental guide to the likelihood of early recurrence. Histological confirmation of node metastases is as valuable as clinical assessment, but is not superior unless other features of node histology are considered. Micrometastases do not increase the probability of early recurrence except in comparison with a group whose nodes lack both metastases and other unfavourable features. The majority of special investigations do not have additional predictive value, though a bone scan is useful in the small number (less than 10%) in whom it is positive.