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The effects of interferon (IFN) treatment on the lipid composition of human peripheral blood lymphocytes or transformed cell line cells were investigated. The major phospholipid classes of lymphocytes as analyzed by 2-dimensional TLC and quantified by phosphorous content were phosphatidylcholine (PC, 43%) and phosphatidylethanolamine (PE, 28%), along with phosphatidylserine (9%) and phosphatidylinositol (8%). The membrane-impermeant reagent, trinitrobenzenesulfonate was used to covalently label cell surface PE. Fatty acid (FA) composition, determined by gas-liquid chromatography, showed a distinct pattern in each lipid class, with a predominance of 16 and 18 carbon fatty acids (FA) in PC and PE respectively. Arachidonic acid (20:4) and, to a lesser extent, docosahexanoic acid (22:6) were predominant in PE. The degree of unsaturation in each class, expressed as the ratio between unsaturated and saturated FA (U/S), was higher in PE (1.72) than in derivatized trinitrophenyl cell surface PE (TNP-PE, 0.57) or PC (0.64). Treatment with IFN resulted in an increased U/S ratio in cell surface PE (1.10) but not in other PE species (1.46). A small increase in unsaturation (0.88) was also observed in PC. Most of the increase in TNP-PE U/S was accounted for by an increase in 20:4 and a concomitant decrease in 18:0. These alterations were observed in the absence of quantitative change in the principal phospholipid classes or in the FA composition of the total lipid extract. In K562, a transformed cell line with characteristics of the erythromyeloid lineage, PE was found to be the most saturated lipid class with a predominance of 18:0. In PC, 16:0 was most abundant. Among unsaturated FA, 18:1 predominated in all lipid classes studied. Treatment with natural IFN alpha for 30 hr generally resulted in a decrease in saturated FA and an increase in unsaturated FA, which was most marked in PE. The U/S ratio in PE was highest in K562 cells during the time of maximal cell proliferation as assessed by tritiated thymidine incorporation. TNP-PE simultaneously decreased. Daudi cells, a B-lymphoblastoid cell line, demonstrated changes in FA composition of lipids with decreased saturated and monoenoic FA after IFN treatment, whereas DIF3 (a clone selected for lack of sensitivity to IFN) showed no change. These studies document changes in membrane FA composition of lymphocytes treated with IFN and correlate IFN-induced changes in transformed cell line FA with effects on proliferation. They further show the existence of a transverse molecular species asymmetry of PE in the plasma membrane of these cells which is altered after IFN treatment.

Seven to eight percent of cervix carcinomas are carcinomas of the cervical stump. The prognosis for these tumors has sometimes been considered more unfavourable than that for carcinomas on intact uterus. From 1976 to 1986 we treated 43 patients with carcinoma of the cervical stump. The mean age was 63.6 years. Staging system used was FIGO classification modified according to the criteria of Institut Gustave Roussy in Villejuif. There were 12 stage IB, 12 early stage II, 5 late stage II and 14 stage III. Twenty-four centropelvic tumors (IB and early stage II) were treated with radiotherapy and surgery, 2 with surgery alone and one with radiotherapy alone. Late stage II and stage III tumors were treated with radiotherapy alone (+ hysterectomy for two patients). Local control rate was 83% for centropelvic tumors and 53% for late stage II and stage III. Seven patients developed distant metastases. Uncorrected 5-year actuarial survival rate was 78% for centro-pelvic tumors and 46% for late stage II and stage III. Three patients developed severe complications (grade 3). Prognostic factors were: stage, nodal status and pathological status of the cervix after radiotherapy. For the same stage the results were similar to those observed for carcinomas on intact uterus treated at our institution during the same time period.

The principal features of the hypotheses presented here are presented in a model (Figure 8). Polyunsaturated phospholipids are preferentially localized on the cytosolic leaflet of the plasma membrane and around proteins. They influence the physical state of these microenvironments and thereby help to regulate cellular functions. Losses of these species due to phospholipase attack, dietary deprivation or other pathological stimuli (such as alcohol), may lead to drastic alterations in some of these functions. The PUFA's released, including 22:6 omega 3, can be metabolised by a lipoxygenase enzyme in the brain and platelet and the products formed are biologically active.

Publisher Summary This chapter discusses the phospholipid metabolism during natural killer cell activity and possible role for transmethylation and phospholipase A2 activation in recognition and lysis. The presumption that NK function might be mediated in part by certain pathways of phospholipid metabolism is derived largely by analogy from other biolgical systems. Phospholipase A2 activity, the generation of lysophosphatidylcholine from phosphatidylcholine, has been suggested as a possible mechanism of lysis of targets by cytotoxic T lymphocytes. In a study described in the chapter, when peripheral blood mononuclear cells were treated with 3-deazadenosine, an inhibitor of transmethylation reactions, in the presence of homocysteine thiolactone, a dose-dependent inhibition of NK activity was observed. In the dose range of effective inhibition of NK activity, phospholipid methylation was inhibited by >50%, without significant effects on protein or nucleic acid methylation. The incorporation of the radioactive methyl group of methionine into peripheral blood mononuclear effector cell phospholipids increased substantially when NK-susceptible target cells were added. Stimulation of phospholipid methylation was not observed when human NK-resistant mouse lymphoma cells were used.

Human blood monocytes incorporated the methyl group from methionine into their neutral lipids. The major methylated product was identified as ubiquinone-50 in monocytes, lymphocytes, and a variety of human tumor cell lines by several analytical procedures including TLC or high performance liquid chromatography and as ubiquinone-45 in a mouse tumor cell line. Up to three methyl groups were shown to be derived from methionine by mass spectrometry. The rate of synthesis of ubiquinone-50 by monocytes as assessed by measuring labeled methyl group incorporation was shown to be linear over a 3-h period. Degradation of ubiquinone proceeded slowly; 80% of the labeled compound persisted after 18 h. The dependence of ubiquinone-50 synthesis upon methionine concentration was established in monocytes, with an estimated apparent Km for methionine of about 20 microM. The tumor promoter, tetradecanoate phorbol acetate, a potent stimulator of superoxide anion (O2-) production in phagocytic cells, inhibited ubiquinone-50 synthesis at nanomolar concentrations in monocytes, but not in lymphocytes, under conditions where oxidation of methionine takes place. Degradation of the labeled ubiquinone was unaffected. Formylmethionylleucyl-phenylalanine, a chemoattractant peptide which stimulates O2- production in phagocytic cells, also inhibited ubiquinone-50 synthesis. The degree of inhibition by either stimulus was increased when the methionine concentration in the medium was low. These findings demonstrate that in human monocytes ubiquinone-50 biosynthesis is regulable and that methionine concentration modulates both its rate of synthesis and the inhibitory effects of two stimuli of O2- production.

Tumoral biological markers of breast cancer expand the predictive value of conventional prognostic factors, such as tumor size, axillary lymph node status, and histoprognostic grade. They include tumor estrogen and progesterone receptor levels, flow cytometric DNA analysis, to convey a prognostic value. Expression of the product of the gene pS2, which reflects the functional integrity of the estradiol receptor, indicates a good prognosis. In contrast, presence of growth factor receptors, such as the EGF receptor, or amplification of the HER2/neu or INT2 oncogene indicate a poor prognosis. Study of protein gp 170 and GST-pi predicts the response of tumors to chemotherapy, while the study of the potential doubling time (Tpot) provides an indication of the renewal capacity of the tumor. Markers of tumor invasiveness and metastatic potential include proteases (activators and inhibitors) produced either by tumor cells or by the cells of the stroma, gene nm 23, and membrane fatty acids. The place of the last markers in patients' treatment is not known yet. The knowledge of the tumor biological parameters along with clinical features should provide an accurate prediction of the aggressiveness of the tumor, allowing the best adjustment of treatment with the expected behavior of the disease.

Historically, castration has been the first endocrine treatment in breast carcinoma. In premenopausal metastatic patients, castration improves quality of survival during a median period of 10 months, in one third of patients. As adjuvant treatment, prophylactic castration can be an alternative to chemotherapy in patients with positive receptors. Prospective randomized trials are being conducted to define indications of each adjuvant treatment.

Between 1976 and 1986 we have treated 396 patients with carcinoma of the uterine cervix, stages Ib, II and III. The mean age was 54.2 years. The staging system used was the FIGO classification, modified according to the Institut Gustave-Roussy criteria. There were in stage Ib 117 cases, in early stage II 124 cases, in late stage II 63 cases and in stage III 92 cases. Treatment methods used were radiotherapy and surgery combined for localised pelvic lesions (stage Ib and stage II) and radiotherapy alone for those cases that were central and going out to the side wall of the pelvis (late stage II and stage III). The actuarial five-year survival rate was 91% for stage Ib, 67% for early stage II, 48% for late stage II and 28% for stage III. The main causes of failure were recurrence in the pelvis in 15% of treated areas and distant metastases in 13%. The state of the lymph nodes was another prognostic factor but the histological subtype and age were not. 7% of cases had severe complications (urinary, digestive and lymphatic).

The prognostic significance of local relapse after conservative treatment of early stage breast cancer has been controversial. To determine the prognostic value of breast relapse occurrence and the factors predisposing to local failure, we analysed the results obtained in a series of 324 patients conservatively treated for breast invasive carcinomas of 2 cm or less. All patients were treated by tumorectomy and axillary dissection, radiation therapy, and adjuvant medical treatment in 85 of 109 patients with involved nodes. The overall 5-yr survival rate was 91.5%. The actuarial 5-yr local control rate was 91.9%. Local relapses occurred in 25 patients. In these patients, the overall 5-yr survival rate was significantly decreased as compared to that of patients without local relapse (76.9% versus 93.4%, P less than 0.001). Recurrence in the breast within 2 yr of initial treatment of severely affected the risk of metastasis occurrence as compared to later relapses (metastasis-free survival rate of 14.3% versus 63.9% at 3-yr from local relapse, P less than 0.01). Local relapse occurred more frequently in premenopausal patients, in patients with low bodymass index, and in patients with small breast size. Local control was not significantly affected by age, tumor size or node involvement. We conclude that the occurrence of a breast relapse after a local conservative treatment has a negative significance and is predictive of a high risk of distant metastasis development, especially when local relapse occurred within 2 yr of initial treatment. There is a need to determine individual factors that could allow discrimination of patients with a high probability of local relapse and subsequent metastasis.

Enlarged colpohysterectomy with lymphadenectomy was performed in 199 patients for cancer of cervix (132 cases), of endometrium (67 cases), of vagina (2 cases) or of tubes (1 case) during combined radiosurgical therapy of these tumors. There was no mortality, the incidence of thrombo-embolic accidents was 3% and urinary fistula was not seen. A lumphocele developed in 7.5% of cases, this level being related to the degree of lymphatic curettage, which should involve not less than 13 glands to avoid lack of efficacy and not more than 20 glands to prevent complications, in cervical cancer. For endometrial cancer, curettage is limited to external iliac obturator glands and retrocrural nodes in young women, and is even omitted in elderly women.

Voltage-gated sodium channels (NaV) are expressed in highly invasive metastatic cancer cells derived from epithelial tissues. In the highly invasive breast cancer cell line MDA-MB-231, we showed that the abnormal expression of NaV1.5 was responsible for a sustained inward sodium current at the membrane potential, which promotes the invasion of the extracellular matrix. We found that NaV1.5 activity leads to a perimembrane acidification, favourable for the pH-dependent proteolytic activity of cysteine cathepsins which play a predominant role in cell invasiveness. Moreover, NaV and the sodium-proton exchanger NHE1 (a pH regulator) seem to be colocalized in specialized lipid rafts domains, caveolae, where cathepsins-B are known to be secreted.Since docosahexaenoic acid (DHA, 22:6 n-3) has been reported to reduce the aggressiveness of some breast cancers, and to be a modulator of ion channels, we investigated its role on NaV activity and cell invasiveness. Supplementation of MDA-MB-231 cells culture medium with 1 µM DHA for five days affected neither cell migration nor proliferation but significantly reduced cell invasiveness, while oleic acid (OA, 18:1 n-9), used as a control, had no effect. Moreover, the combination of DHA with tetrodotoxin (specific NaV blocker) demonstrated no further effect on invasion, suggesting a possible regulation of NaV activity by DHA. Indeed, NaV currents were reduced with DHA but not with OA supplementation. These fatty acids were inefficient to reduce sodium currents when acutely applied, suggesting a middle- or long-term regulation of NaV channels. However, no effect on NaV mRNA or protein expression and no change in NaV raft localization was observed.Thus, DHA effects could occur through a modification in cholesterol/phospholipids composition of the plasma membrane and/or a modification in factors regulating NaV channels activity and/or addressing to the plasma membrane.

Background NaV1.5 voltage-gated sodium channels are abnormally expressed in breast tumours and their expression level is associated with metastatic occurrence and patients’ death. In breast cancer cells, NaV1.5 activity promotes the proteolytic degradation of the extracellular matrix and enhances cell invasiveness. Findings In this study, we showed that the extinction of NaV1.5 expression in human breast cancer cells almost completely abrogated lung colonisation in immunodepressed mice (NMRI nude). Furthermore, we demonstrated that ranolazine (50 μM) inhibited NaV1.5 currents in breast cancer cells and reduced NaV1.5-related cancer cell invasiveness in vitro. In vivo, the injection of ranolazine (50 mg/kg/day) significantly reduced lung colonisation by NaV1.5-expressing human breast cancer cells. Conclusions Taken together, our results demonstrate the importance of NaV1.5 in the metastatic colonisation of organs by breast cancer cells and indicate that small molecules interfering with NaV activity, such as ranolazine, may represent powerful pharmacological tools to inhibit metastatic development and improve cancer treatments. Electronic supplementary material The online version of this article (doi:10.1186/1476-4598-13-264) contains supplementary material, which is available to authorized users.