PTEN protein expression in postmenopausal steroid receptor positive early breast cancer patients treated with adjuvant tamoxifen.

PURPOSE: Since one of possible causes of resistance to antiestrogen therapy in steroid receptor positive (SR+) breast cancer (BC) patients is an alteration of PTEN (phosphatase and tensin homolog deleted on chromosome 10) signaling pathways, the aim of this study was to determine the PTEN protein expression in postmenopausal patients with steroid SR+ BC treated with adjuvant tamoxifen, to investigate the association of PTEN protein expression with tumor histology, size and grade, estrogen receptor (ER), progesterone receptor (PR) and human epidermal growth factor receptor 2 (HER2) statuses and disease outcome. METHODS: This was a retrospective analysis of 78 postmenopausal stage I/II SR(+)BC patients treated with adjuvant tamoxifen. PTEN protein expression and ER, PR and HER2 status were determined using immunohistochemistry. RESULTS: The distribution of PTEN protein expression according to tumor histology was as follows: PTEN+ status in 27/43 (62.8%) patients with ductal and in 26/35 (74.3%) patients with lobular carcinomas; and PTEN(-) status in 16/43 (37.2%) patients with ductal and in 9/35 (25.7%) patients with lobular carcinomas. Disease relapse was observed in 38/78 patients: 14/53 (26.4%) of PTEN(+) BC subgroup and 24/25 (96%) of PTEN(-) subgroup (x(2), p=0.018). There were no significant associations between PTEN protein expression and tumor histology, size and grade, and ER, PR and HER2 expression. Patients with PTEN(-) had significantly shorter disease-free interval (DFI) and overall survival (OS) (for both, log rank test, p <0.01) compared to PTEN(+) BC patients. CONCLUSION: Our results suggest that PTEN protein expression might be of prognostic significance in postmenopausal SR(+) BC patients treated with adjuvant tamoxifen.

Humoral immunity to cow's milk proteins and gliadin within the etiology of recurrent aphthous ulcers?

OBJECTIVES: The goal of this study was to determine the incidence of serum antibodies to gliadin and to cow's milk proteins (CMP) using ELISA test, within patients who have recurrent aphthous ulcers (RAU). SUBJECTS AND METHODS: Fifty patients with recurrent aphthous ulcers and fifty healthy people were included in this research. Levels of serum IgA and IgG antibodies to gliadin and IgA, IgG and IgE to CMP were determined using ELISA. RESULTS: The levels of serum antigliadin IgA and IgG antibodies were not significantly higher in patients with RAU in comparison with the controls (P = 0.937 and P = 0.1854 respectively). The levels of serum anti-CMP IgA, IgG and IgE antibodies were significantly higher in patients with RAU in comparison with the controls (P < 0.005, P < 0.002 and P < 0.001 respectively). In general, the increased humoral (IgA or IgG) immunoreactivity to CMP was found in 32 of 50 patients, while 17 of them showed the increased levels of both IgA and IgG immunoreactivity to CMP. At the same time, 16 out of 50 patients had IgA, IgG and IgE immunoreactivity to CMP. CONCLUSION: These results indicate the strong association between high levels of serum anti-CMP IgA, IgG and IgE antibodies and clinical manifestations of recurrent aphthous ulcers.

Radiotherapy-induced changes of peripheral blood lymphocyte subpopulations in cervical cancer patients: relationship to clinical response.

PURPOSE: To determine the absolute number and percentage of peripheral blood lymphocyte subpopulations positive (+) cells CD8(+), CD8(+)NKG2D(+), CD8(+), Granzyme B(+) (GrB), CD16(+), CD16(+)NKG2D(+), CD56(+) and CD56(+)NKG2D(+) in cervical cancer patients before and after radiotherapy (RT), and to analyze whether their changes are related to the clinical response. MATERIALS AND METHODS: Stage IIB - IVA cervical cancer patients received external irradiation and concomitant intracavitary brachytherapy. Blood samples for immunophenotypic analysis by flow cytometry were collected from each patient one day before starting RT and one day after completing RT. Fifteen healthy volunteers served as controls. Surface marker expression and granzyme B positivity were quantified on FACSCalibur flow cytometer. RESULTS: Unlike their absolute numbers, the percentages of all analyzed lymphocyte subsets of all patients, including those with complete response (CR), were significantly increased (p <0.05) after RT. Only in patients with progressive disease (PD), CD8(+), CD8(+)NKG2D(+), CD16(+) and CD56(+)NKG2D(+) lymphocytes were not significantly increased. In healthy volunteers, the percentage of CD8(+)GrB(+) lymphocytes was lower than in patients after RT, while the percentages of CD56(+) and CD56(+)NKG2D(+) cells were higher than in patients before RT (p <0.05). CONCLUSION: Our data indicate that RT, besides its direct cytoreductive effect on tumor cells, may contribute to better immunological control of cervical cancer.

Inhibition of proliferation on some neoplastic cell lines-act of carvedilol and captopril.

The present work examines the effects of beta and alpha1-adrenoceptor antagonist carvedilol, and angiotensin converting enzyme (ACE) inhibitor captopril, on in vitro growth of tumor cell lines derived from breast tumor (MDA-MB-361), melanoma (Fem-x), cervix adenocarcinoma (HeLa) and human myelogenous leukemia (K562). Carvedilol or captopril were applied on malignant cells at 0.1, 1, 5, 10 and 50 micromol. Cell survival was determined 48 hrs after drugs action by MTT. On all cell lines tested, carvedilol was a very potent inhibitor of cell proliferation. The order of sensitivity of various human cell lines to carvedilol's antiproliferative action was: myelogenous leukemia K562 (IC50 = 22.66 +/- 2.14 micromol), > cervix carcinoma HeLa (IC50 = 30.56 +/- 5.16 micromol), > melanoma Fem-x (IC50 = 32.17 +/- 5.75 micromol), > breast tumor MDA-MB-361 (IC50 = 35.04 +/- 2.95 micromol). In contrast, captopril, used in doses from 0.1-50 micromol, was ineffective (IC50 > 50 micromol) to the same cell lines. It is important to note that captopril in concentrations > 1 micromol led to a statistically significant increase in the percent of survived melanoma Fem-x cells (p < 0.05). Understanding the action of these established and clinically accepted agents could provide a basis for design of improved therapeutic regimens in the treatment of cancer diseases.

Cytotoxic and antioxidant activity of Achillea alexandri-regis.

The cytotoxicity and antioxidant properties of herb extracts of Achillea alexandri-regis were studied. Combined chloroform and ethylacetate extracts exhibited a pronounced cytotoxic effect against HeLa cancer cells (IC50 = 25.92 +/- 4.96 microg/ml), and lower cytotoxicity against K562 leukemia cells (IC50 = 48.59 +/- 18.31 microg/ml). The methanol extract was found to be a moderately cytotoxic in vitro agent against HeLa and K562 cells. No suppressive activity was detected on non-malignant peripheral blood mononuclear cells (PBMC). The antioxidant activity of the methanol extract was assessed by DPPH radical scavenging. The methanol extract of A. alexandri-regis showed concentration dependent DPPH radical scavenging activity with IC50 = 36.14 +/- 0.05 microg/ml.

Cholic acid derivatives as 1,2,4,5-tetraoxane carriers: structure and antimalarial and antiproliferative activity.

Cholic acid-derived 1,2,4,5-tetraoxanes were synthesized in order to explore the influence of steroid carrier on its antimalarial and antiproliferative activity in vitro. Starting with chiral ketones, cis and trans series of diastereomeric tetraoxanes were obtained, and the cis series was found to be approximately 2 times as active as the trans against Plasmodium falciparum D6 and W2 clones. The same tendency was observed against human melanoma (Fem-X) and human cervix carcinoma (HeLa) cell lines. The amide C(24) termini, for the first time introduced into the carrier molecule of a tetraoxane pharmacophore, significantly enhanced both antimalarial and antiproliferative activity, as compared to the corresponding methyl esters, with cis-bis(N-propylamide) being most efficient against the chloroquine-susceptible D6 clone (IC(50) = 9.29 nM). cis- and trans-bis(N-propylamides) were also screened against PBMC, and PHA-stimulated PBMC, showing a cytotoxicity/antimalarial potency ratio of 1/10 000.

Humoral immunity in patients with carcinoma of the uterine cervix--effects of radiation therapy.

The parameters of nonspecific immunity-serum immunoglobulins and immune complexes--were evaluated in patients with carcinoma of the uterine cervix (Stages IIB and IIIB) prior to, during and immediately after pelvic irradiation. In untreated patients, significantly elevated circulating IgA was found only in patients in Stage IIIB; serum IgG and IgM in both groups did not differ from control values. The level of circulating immune complexes in both groups was higher than in controls. Radiotherapy did not affect significantly any of the parameters examined; only the percentage of patients with elevated concentrations of IgA and IgG decreased during the treatment. These results showed that fractionated pelvic irradiation did not affect B cell function, these cells being more radioresistant than other lymphocyte subpopulations.

Immune reactive proteins in patients irradiated for cervical cancer. One year follow up.

The parameters of nonspecific humoral immunity--serum immunoglobulins and immune complexes--were evaluated in irradiated group of patients with uterine cervix carcinoma (Stages IIB and IIIB), during one year follow up. The concentrations of IgA, which were elevated in patients before therapy, slowly declined after the radiotherapy, at the end of the follow up being returned to the normal range. The concentrations of IgG, which were significantly decreased in patients immediately after the therapy, were sharply and transiently elevated two months after the therapy; afterwards, the levels of IgG gradually decreased to the values which did not differ from their pre- or post-RT levels, as well as from control ones. The levels of CIC were not significantly changed after radiotherapy, although a transient increase was found seven months after radiotherapy, being not different from controls at the end of the follow up. The serum IgM remained in the range of control values immediately after radiotherapy, as well as during monitoring. The slow normalization of the serum IgA and CIC levels might reflect the success of the therapy.

Immune reactive proteins in renal cell carcinoma patients treated by IFN alpha alone or in combination with vinblastine.

Immunoreactive proteins--serum immunoglobulins and immune complexes were evaluated in renal cell carcinoma (RCC) patients. The analyses were done after radical nephrectomy before, at the end, and six months after the therapy, with IFN alpha alone (in patients in Stage II) or IFN alpha in the combination with vinblastine (in patients in Stage III and IV of the disease). Data obtained before immuno- or immunochemotherapy show significant increase in IgG and IgA concentrations in RCC patients in all stages of the disease investigated--in comparison to controls, while circulating immune complexes were significantly elevated only in patients in the advanced Stages of the disease (III and IV). The unchanged IgM level was found in all untreated RCC patients regarding the controls. Immuno- or immunochemotherapy did not affect the immunoreactive proteins (Ig and CIC) in the investigated patients, without respect to their clinical response to the applied therapy.

Amine oxidase-mediated cytotoxicity of spermine and epinephrine to human myelogenous leukemia K562 cells.

The effects of spermine and beta-adrenoceptor agonists (epinephrine, terbutaline and orciprenaline) in the presence and in the absence of fetal bovine serum (FBS) on human myelogenous leukemia K562 cells viability (V) and survival (N/Nc) were examined. Spermine-FBS significantly decreased both V and N/Nc of K562 cells. Aminoguanidine (AG), an amine oxidase inhibitor, and reduced form of glutathione abolished this effect demonstrating that the spermine-FBS action was amine oxidase-mediated. Epinephrine expressed a strong cytotoxicity to K562 cells which was abolished by pargyline, a specific monoamine oxidase (MAO) inhibitor, as well as by reduced form of glutathione. Terbutaline and orciprenaline exerted no cytotoxic activity to K562 cells cultured in FBS-supplemented medium, independently on the presence of spermine. However, terbutaline at concentrations of over 1 mmol strongly inhibited the cytotoxic effect on spermine-FBS. The relationship between cytotoxicity and chemical structure of beta-adrenoceptor agonists was discussed especially with respect to their stability toward oxidation.

To the mechanism of spermine-FBS cytotoxicity toward K562 human myelogenous leukemia cells.

The effects of several compounds acting through adenylate cyclase system and/or influencing prostaglandin biosynthesis on spermine-FBS cytotoxicity to human myelogenous leukemia K562 cells were studied. Salbutamol, a beta 2-adrenoceptor agonist inhibited to a certain extent spermine-FBS cytotoxic action to K562 cells, and propranolol, a beta 2-adrenoceptor antagonist, did not affect this inhibition. Aminophylline, an inhibitor of cyclic nucleotide phosphodiesterase, acted suppressing spermine-FBS cytotoxicity to K562 cells. Pretreatment of the cells with dexamethasone did not significantly alter salbutamol-related inhibition of spermine-FBS cytotoxicity. Indomethacin, an inhibitor of cyclooxygenases directly involved in prostaglandin biosynthesis, did not interfere with protective terbutaline effects against spermine-FBS cytotoxicity to K562 cells during the 24-hour period.

Lyophilized whole human melanoma cells stimulate human PBMC proliferation and enhance suppressive action of PBMC toward survival of the same malignant cell line in vitro.

The goal of this work was to determine: a) do lyophilized human melanoma BG or Fem-X cells affect the proliferative capacity of normal human peripheral blood mononuclear cells (PBMC) and b) does the PBMC six-days preincubation in nutrient medium with FBS with, or without lyophilized human melanoma BG or Fem-x cells, affect their suppressive action on the survival of the same malignant cell line in vitro. In the aim to avoid any stimulating effect of FBS, other group of experiments were done in nutrient medium with human AB serum in order to determine: c) does the PBMC six-day-preincubation with lyophilized human melanoma BG or Fem-x cells affect their antiproliferative action on the corresponding malignant cell line in vitro and d) does the PBMC six-day preincubation with lyophilized normal PBMC, obtained from healthy volunteer (as a source of allogenous, but not of tumor antigens), affect their suppressive action on the survival of both melanoma BG and Fern-x cell lines in vitro. Results obtained in the presence of FBS in nutrient medium, showed that lyophilized BG cells induced a proliferation of the healthy PBMC, depending on the number of stimulating lyophilized cells. Lyophilized Fem-x cells induced healthy PBMC proliferation in lesser degree than lyophilized BG cells. This stimulation was almost constant, not dependent on the number of stimulating lyophilized Fem-x cells. Six-day stimulation in vitro by both lyophilized melanoma cells enhanced the suppressive action of PBMC on the survival of the corresponding malignant cell line. Experiments done in nutrient medium with normal human AB serum showed that six-day stimulation with lyophilized melanoma cells enhanced, again, the suppressive action of PBMC on the survival of the corresponding malignant cell line. Contrary, six day preincubation of normal PBMC with the lyophilized healthy PBMC (obtained from other healthy person) inhibited their suppressive action on the survival of both malignant cell lines in vitro.

The influence of surgery and anesthesia on lymphocyte functions in breast cancer patients: in vitro effects of indomethacin.

Surgical trauma and anesthesia may lead to the postoperative immunosuppression, the exact mechanism of which is still unresolved. Among various factors, the role of prostaglandine PGE2-mediated suppression was also proposed. We investigated the influence of surgery and two anesthetic regimes on lymphoproliferative response (LPR) to PHA and on NK cell activity (MTT) in breast cancer patients, as well as the effect of indomethacin, a PGE2 synthesis inhibitor, on these lymphocyte functions in vitro. In 36 previously untreated patients the lymphocyte functions were assayed before, 24 hours and seven days after the surgery. In regard to LPR, three distinct response patterns were observed: a) significant (p < 0.05) increase of initially lowered LPR; b) significant (p < 0.001) decrease of initially normal LPR 24 hours after operation, followed by normalization after seven days; c) no change of initially normal LPR. Indomethacin in vitro significantly (p < 0.05) enhanced the diminished LPR only before surgery, no effect being seen after the operation. The NK cell function was unaffected by surgery regardless the initial level of activity. Indomethacin had no effect on this lymphocyte function. There was no difference between the patient groups submitted to the different anesthetic regimes. In conclusion, our results show that surgical trauma variably affect the lymphocyte functions of cancer patients, the effect not being related to the particular anesthetic regime used. The PGE2-mediated suppression is not likely to be involved in postoperative immune function impairment.

Antimelanoma immunity in vitiligo and melanoma patients.

Cutaneous melanoma and vitiligo are diseases etiology of which evolves around melanocytes. The nature of immunological disturbances associated with these diseases is not elucidated. The experiments performed in this work were aimed to determine antimelanoma immunotoxicity in patients with melanoma and patients with vitiligo. Twelve patients with melanoma, ten patients with vitiligo and seventeen healthy volunteers were studied. The cytotoxicity of PBMC was evaluated indirectly through determination of target melanoma (Fem-x) or control tumor (HeLa) cell survival, in the presence of 15% of AB or autologous sera, by MTT test. The mean values of antimelanoma cytotoxicity in AB serum were similar in both patients groups and in controls. However, the frequency of patients with the enhanced cytotoxicity against melanoma cells, in relation to control tumor cells, was lower in both patients groups than in controls. The intensity of antimelanoma cell-mediated cytotoxicity in melanoma patients, in the presence of autologous serum, was significantly lower in comparison to that found in control subjects and vitiligo patients (p<0.014, in both cases). This indicates that some factors from melanoma patient's sera contribute to impairment of the cytotoxicity of autologous PBMC, while other factors from the serum of vitiligo patients and control subjects enhanced their PBMC antimelanoma cytotoxicity.

Adenosine contributes to the amine oxidase-mediated spermine cytotoxicity to human myelogenous leukemia K562 cells.

The effects of adenosine, aminophylline, dipyridamole and salbutamol on the amine oxidase-mediated spermine cytotoxicity to KS62 human myelogenous leukemia cells without Ph-chromosome, spontaneously enriched with mildly adherent cells, were studied. In the absence of spermine, adenosine expressed very mild inhibitory action on K562 cell survival, while in combination with the polyamine an almost additive increase in spermine-FBS cytotoxicity was observed. Aminophylline and salbutamol attenuated both spermine-FBS and spermine-FBS-adenosine suppression of cell survival and viability when equimolar concentration of these agents and the adenosine were applied. Pre-treatment of the cells with higher adenosine levels, in the presence of either aminophylline or dipyridamole, or salbutamol, was associated with decreased K562 cell survival, with the appearance of morphological changes in 10-20% of cells. Additional spermine-FBS cytotoxic effect was not observed in cells pre-treated with adenosine-aminophylline, or adenosine-salbutamole, but morphological changes in 10-20% of cells, even in the presence of spermine, was observed again. Dipyridamole alone suppressed very weakly K562 cell survival. In cells pretreated with dipyridamole, in the presence of spermine-FBS, an additive decrease in cell survival was observed. Pre-treatment of cells with dipyridamole and adenosine in presence of spermine-FBS did not result in a decrease of cell survival compared to the one obtained in dipyridamole-spermine-FBS treated cells.

The mechanism of 8-Cl-cAMP action.

8-Chloroadenosine 3',5'-monophosphate (8-Cl-cAMP) is a potential new anticancer agent, but its mechanism of action is not clearly defined. In this work we have studied the effect of various heat inactivated and heat untreated human sera in the absence or in the presence of a nonspecific phosphodiesterase (PDE) inhibitor, IBMX, or of nucleoside transport inhibitor and cGMP-specific PDE inhibitor dipiridamole (DP), or of inosine-monophosphatedehydrogenase (IMPDH) inhibitor, tiazofurin, (T), on the antiproliferative 8-Cl-cAMP action towards two human malignant cell lines, K562 and HeLa cells, in vitro. Cell survival was determined 72 hrs after the agents action, using MTT assay. The results obtained, indicated the similar inhibitory effect of 8-Cl-cAMP on HeLa cell survival in the presence of four different heat untreated human sera (IC50 = 4-4.8 microM). Serum heat inactivation caused decrease in 8-Cl-cAMP antiproliferative action depending on the blood donor (IC50 = 23 microM, 15 microM, 19 microM, and 9 microM) and suggesting that some thermolabile ingredient(s) present in sera is involved, at least partially, in the induction or permittance of antiproliferative 8-Cl-cAMP action. K562 Cells were not as much resistant to 8-Cl-cAMP as HeLa cells, or mouse melanoma B16 cells; in the presence of heat untreated FBS, IC50 = 16 microM, while for B16 cells IC50 was 8 microM. Different human sera show different effect on 8-Cl-cAMP action on K562 cells: IC50 = 7.5 microM and 16.5 microM. In the presence of heat inactivated human sera 8-Cl-cAMP IC50 concentrations were higher, with relevant mutual differences. The effect of different sera on 8-Cl-cAMP action was only partly abrogated in the presence of a nonspecific PDE inhibitor, IBMX, suggesting that the serum PDE action is one of the various factors contributing to the induction of 8-Cl-cAMP antiproliferative action. Nucleoside transport inhibitor and cGMP-specific PDE inhibitor dipiridamole inhibited the antiproliferative 8-Cl-cAMP action to HeLa and K562 cells. Tiazofurin and 8-Cl-cAMP acted as antagonists on HeLa, but not on K562 cells.

Antiproliferative activity of some cis-/trans-platinum(II) complexes on HeLa cells.

Purpose of this work was to synthesize several cis-/trans- isomer pairs of the platinum(II) complexes, and study the extent and the mode of their antiproliferative activity on HeLa cells. Six platinum(II) isomer pairs have a general formula cis-/trans-[PtA2X2], where A is ligand: ammonia (NH3), pyridine (Py); and X is ligand: chloride ion (Cl-), bromide ion (Br-), iodide ion (I-), thiocyanato ion (SCN-); four compounds have different structural formulas, and these are cis-/trans-[Pt(NH2OH)2(NH3)2]Cl2, and cis-/trans-Pt(Gly)2, where Gly is bidentate glycinato ligand. Results of the MTT assay, showed that six cis- and one trans-platinum(II) complexes exhibited cytotoxicity (IC50) ranging between 5 and 33 microM. Most of the cis-platinum(II) isomers caused significant alteration of cell cycle phases progression, and induced apoptosis in degree that varied among different compounds, as evaluated using flowcytometry and morphological study. Spectrophotometric analysis (AAS) indicated that there is no correlation between intracellular platinum(II) accumulation and cytotoxicity of tested complexes.

Antiproliferative action of isatine-beta-thiocarbohydrazone and N-ethylisatine-beta-thiocarbohydrazone on human PBMC and on two neoplastic cell lines.

The antiproliferative action of two synthetic compounds, isatine-b-thiocarbohydrazone (IsTCH) and N-ethyl isatine-beta-thiocarbohydrazone (N-Et-IsTCH), towards healthy human peripheral blood mononuclear cells (PBMC) and two neoplastic cell lines in vitro, was investigated. IsTCH and N-Et-IsTCH were dissolved in DMSO and then diluted with nutrient medium to desired final concentration. Target cells were PBMC, as well as human cervix carcinoma - HeLa cells, and murine melanoma B16 cells. Five different concentrations (3 microM to 50 microM) of investigated agents were applied on target cells. Cell survival was determined 72 h after the agent's action using MTT test. Results obtained showed that both investigated compounds exerted a dose dependent antiproliferative action to neoplastic cell lines. Their action was only cytostatic; trypan blue exclusion test did not show any sign of direct drug cytotoxicity when drugs concentration were less than 50 microM. ICs50 +/- SD for IsTCH antiproliferative action were 61.69 +/- 4.25 microM for HeLa cells; 34.1 +/- 7.15 microM for B16 cells: 17.62 +/- 7.11 microM for nonstimulated and 30.0 +/- 9.46 microM for stimulated (by 5 mg/ml PHA) PBMC. ICs50 +/- SD for the action of N-Et-IsTCH were 21.86 +/- 1.77 microM for HeLa cells; 10.37 +/- 1.55 microM for B16 cells; >47 microM for both, nonstimulated and for stimulated, PBMC. Nonstimulated human PBMC appeared to be the most sensitive to the cytostatic IsTCH action; while HeLa cells were the most resistant. N-Et-IsTCH showed more than two or five fold stronger antiproliferative effect toward B16 cells than on HeLa or PBMC cells, respectively, and more than three times intensive activity compared to IsTCH, indicating specificity of N-Et-IsTCH towards inhibition of melanoma cell growth. While increasing concentrations of IsTCH led to decrease in the the PBMC induced suppression of HeLa cell survival; N-Et-Is-TCH in the difference from IsTCH, in dose dependent way contributed to the PBMC induced suppression of HeLa cell survival. In conclusion, the activity of N-Et-Istch on malignant melanoma cells deserves further investigation.

Effects of X-ray irradiation on the overexpression of HER-2/Erb-B2 on breast cancer cell lines.

Irradiation is the conventional treatment modality for cancer patients. However, besides its cytotoxic effects on malignant cells it might also affect the biology of surviving cells. Since overexpression of HER-2 receptors on malignant cells is a prerequisite for the therapeutic efficacy of Herceptin, it seems important to know whether previous irradiation changes their overexpression. The experiments performed in this work were aimed to determine whether X-ray irradiation of MDA-MB-361 and MDA-MB-453 breast carcinoma cell lines, besides its cytotoxic action, affects the overexpression of HER-2 protein. Determination of the cytotoxic effect of X-ray irradiation was done using trypan blue test. The breast carcinoma cell responsiveness to herceptin treatment in the presence of 10% fresh human serum (from healthy volunteer's) in the presence or absence of 25 microg/ml of herceptin, in vitro before and after cell-irradiation, was evaluated by MTT test. The degree of HER-2 overexpression was determined by immunocytochemistry, using DAKO HercepTest. Preliminary results obtained in this work showed that X-ray irradiation, besides its cytotoxic effect on malignant cells, could lead to overexpression of HER-2 receptors on (initially by immunocytochemistry, HER-2 negative) tumor cells, indicating change in biology of treated tumor cells. Further investigation in this direction will probably be helpful to elucidate this task in order to improve the selection of irradiated patients for Herceptin therapy.

T-2 toxin affects proliferation of three different neoplastic cell lines.

The antiproliferative effect of T-2 toxin (T-2) towards mouse melanoma B16 cells, human myelogenous leukemia K562 cells, and human cervix carcinoma, HeLa cells, was studied. For the first four days of T-2 presence B16 cell survival was decreased in dose dependent fashion. However, cell survival after eleven days T-2 action may be dual: some stimulation of cell growth that was direct function of the number of seeded cells per well was observed and cell survival (for the highest number of seeded cells) six times greater than control, was noticed at 20 nM T-2 toxin concentration. A smaller cell growth stimulation (cell survival more than 3 times higher than control) was observed with a lower cell number seeded per well. Nevertheless, by eleventh day concentrations of T-2 higher than 35 nM completely inhibited B16 cell proliferation. The same trend was noticed for T-2 action towards K562 cells. Treatment of HeLa cells with various T-2 concentrations led to a marked inhibition of cell survival that was more pronounced at the end of 44th or 72nd hour, than after the 20th hour of agent's action. ICs50 values obtained in the present work, suggest that B16 cells were the most sensitive to T-2 antiproliferative action, while HeLa cells were the most resistant. When PBMC were cultured with HeLa cells the antagonism against various T-2 concentrations was observed; cell survival determined after 44, or 72 hours of cells incubation, was less decreased compared to cultures treated with T-2, or with PBMC only. In addition, it was shown that T-2 and cis-DDP had an antagonist effect on HeLa cells survival.