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A cancer patient who smokes is a very fragile person and we identify in scientific literature three main areas of clinical practice and research to develop the care of smokers with cancer. (i) Telling facts: smoking impacts on the survival and on the outcomes of surgery, chemo-, radio- and biological therapies. The aim of our intervention was to enable patients to make informed choices about smoking. (ii) Offering sensitive and effective smoking cessation like an instrument of patient empowerment to motivate change in smoker patient lifestyle. (iii) Assisting smoker patients if they develop acute nicotine withdrawal symptoms. Smoking care and nicotine replacement therapy can support temporary abstinence during the inpatient stay and providing patients with an opportunity for smoking cessation can prompt a future permanent quit attempt. Comprehensive cancer centers must act like a promoter of a better smokers' care, applying guidelines to their reality and try to do more research on smokers' needs and on the resources to assist them. Only the alliance between victims of smoking addiction and health personnel can give a chance against the tobacco epidemic.

Background: It has been reported that KRAS mutations (and to a lesser extent KRAS mutations with the BRAF V600E mutation) negatively affect response to anti-epidermal growth factor receptor (EGFR) mAbs in metastatic colorectal cancer (mCRC) patients, while the biological impact of the EGFR pathway represented by PI3K/PTEN/AKT on anti-EGFR treatment is still not clear., Patients and Methods: We analysed formalin-fixed samples from a cohort of 32 mCRC patients treated with cetuximab by means of EGFR immunohistochemistry, EGFR and PTEN FISH analysis, and KRAS, BRAF, PI3KCA, and PTEN genomic sequencing., Results: Ten (31%) of 32 patients showed a partial response to cetuximab and 22 (69%) did not [nonresponder (NR)]. EGFR immunophenotype and FISH-based gene status did not predict an anti-EGFR mAb response, whereas KRAS mutations (24%) and PI3K pathway activation, by means of PI3KCA mutations (13%) or PTEN mutation (10%)/loss (13%), were significantly restricted to, respectively, 41% and 37% of NRs., Conclusion: These findings suggested that KRAS mutations and PI3KCA/PTEN deregulation significantly correlate with resistance to cetuximab. In line with this, patients carrying KRAS mutations or with activated PI3K profiles can benefit from targeted treatments only by switching off molecules belonging to the downstream signalling of activated EGFR, such as mammalian target of rapamycin.

Experimental evidence has shown, both in vitro and in animal models, that neoplastic growth and subsequent metastasis formation depend on the tumor's ability to induce an angiogenic switch. This requires a change in the balance of angiogenic stimulators and inhibitors. To assess the potential role of angiogenesis factors in human thyroid tumor growth and spread, we analyzed their expression by semiquantitative RT-PCR and immunohistochemistry in normal thyroid tissues, benign lesions, and different thyroid carcinomas. Compared to normal tissues, in thyroid neoplasias we observed a consistent increase in vascular endothelial growth factor (VEGF), VEGF-C, and angiopoietin-2 and in their tyrosine kinase receptors KDR, Flt-4, and Tek. In particular, we report the overexpression of angiopoietin-2 and VEGF in thyroid tumor progression from a prevascular to a vascular phase. In fact, we found a strong association between tumor size and high levels of VEGF and angiopoietin-2. Furthermore, our results show an increased expression of VEGF-C in lymph node invasive thyroid tumors and, on the other hand, a decrease of thrombospondin-1, an angioinhibitory factor, in thyroid malignancies capable of hematic spread. These results suggest that, in human thyroid tumors, angiogenesis factors seem involved in neoplastic growth and aggressiveness. Moreover, our findings are in keeping with a recent hypothesis that in the presence of VEGF, angiopoietin-2 may collaborate at the front of invading vascular sprouts, serving as an initial angiogenic signal that accompanies tumor growth.

Background: We previously reported the case of a patient affected with Denys-Drash syndrome (DDS), who developed disseminated EBV-related Burkitt's lymphoma (BL) after kidney transplantation. Here, we describe the molecular characterisation of the WT1 gene in the constitutional and tumour DNA of this patient., Patients and Methods: WT1 exons 2 to 10 were sequenced in constitutional and tumour DNAs. By Southern blotting the latter was also investigated for the presence of gene rearrangements. Gene expression analysis in tumour cells was performed by reverse transcriptase-polymerase chain reaction (RT-PCR)., Results: A germline missense mutation affecting one of the zinc finger domains of the gene, and previously reported in other DDS cases, was observed. No alterations of the constitutionally wild-type WT1 allele and no expression of the gene were observed in BL cells. A small group of BLs from other paediatric patients showed a variable expression of WT1., Conclusions: Our findings indicate that WT1 is unlikely to be involved in the onset of BL in our case. However, a possible role of the gene in at least a subset of these lymphoproliferative diseases may be suggested.

Neoplastic growth is usually dependent on blood supply, and it is commonly accepted that this is provided by the formation of new vessels. However, tumors may be able to grow without neovascularization if they find a suitable vascular bed available. We have investigated the pattern of vascularization in a series of 500 primary stage I non-small-cell lung carcinomas. Immunostaining of endothelial cells has highlighted four distinct patterns of vascularization. Three patterns (which we called basal, papillary, and diffuse) have in common the destruction of normal lung and the production of newly formed vessels and stroma. The fourth pattern, which we called alveolar or putative nonangiogenic, was observed in 16% (80/500) of the cases and is characterized by lack of parenchymal destruction and absence of both tumor associated stroma and new vessels. The only vessels present were the ones in the alveolar septa, and their presence highlighted, through the whole tumor, the lung alveoli filled up by the neoplastic cells. This observation suggests that, if an appropriate vascular bed is available, a tumor can exploit it and grows without inducing neo-angiogenesis. This could have implications for strategies aimed at inhibiting tumor growth by vascular targeting or inhibition of angiogenesis.

A good experimental model of genetic predisposition to hepatocellular tumors is the murine strain C3H. These tumors share morphologic similarities with human hepatocellular tumors. After a treatment with a single small dose of chemical carcinogen, the C3H mice show a high susceptibility to the growth of hepatocellular neoplastic lesions, that reach a volume > 100-fold as compared to the corresponding lesions of genetically resistant strains. Genetic linkage analysis experiments were conducted in 2 different crosses, with the C3H as one of the parental strains, and the other parental strains being represented by mice genetically resistant to hepatocarcinogenesis (A/J, M. spretus). Six different regions, on chromosomes 2, 5, 7, 8, 12, and 19 showed a significant linkage with hepatocellular tumor development. These results provide the genetic basis for the strain variations seen in susceptibility to hepatocarcinogenesis, indicating polygenic inheritance of this trait.

The cancer chemopreventive retinoid N-(4-hydroxyphenyl)-all-trans retinamide (HPR) was recently shown by us to have antiproliferative and apoptotic effects on human leukemic cell lines, including those unresponsive to all-trans retinoic acid (ATRA). We have now characterized further the process of HPR-induced cell death. We report that inhibitors of RNA transcription and of protein synthesis, activators of protein kinase C (PKC), inhibitors of tyrosine kinases, Zn++, and the antioxidants acetylcysteine, ascorbic acid, alpha-tocopherol, and deferoxamine suppressed HPR-induced apoptosis. HL60 cells induced toward monocytic differentiation by 1,25 dihydroxyvitamin-D3 [1,25(OH)2D3], but not those induced toward the granulocytic differentiation by ATRA, showed reduced responses to HPR. The transport of HPR by cells with different sensitivity to the retinoid, however, was similar, even after treatment with the phorbol ester 12-O-tetradecanoylphorbol-13-acetate (TPA), which induces unresponsiveness to HPR. The expression of the apoptosis-related genes bcl-2, p53, and c-myc was examined to determine their role in HPR-triggered cell death. The levels of bcl-2 mRNA were markedly diminished by 24 hours of HPR treatment in all cell lines except in the relatively HPR-insensitive line K422. However, probably because of its long half-life, bcl-2 protein levels were either unchanged or only slightly decreased. Downregulation of p53 mRNA was also observed within 24 hours of HPR exposure in NB4 but not K422 cells, but no changes in the amount of p53 protein were found. Suppression of c-myc transcription was observed in all cells except K422. The protective role of bcl-2 on cell death by HPR was investigated in HL60 as well as 697 pre-B leukemia and Jurkat T-acute lymphocytic leukemia (T-ALL) cells constitutively expressing high levels of bcl-2 proteins due to gene transfer manipulation. Compared with control cells, the onset of apoptosis in these cells with deregulated bcl-2 production was delayed by at least 24 hours. These findings establish that cell death by HPR requires RNA transcription and protein synthesis and is regulated by the activation of PKC. Although changes in bcl-2, p53, and c-myc expression are found in cells treated with HPR, the time-course of these events suggests that HPR-triggered apoptosis is not directly controlled by these genes. Finally, while ectopic overexpression of bcl-2 does not protect cells from death by HPR, it markedly delays its onset.(ABSTRACT TRUNCATED AT 400 WORDS)

Freshly cultured vascular endothelial cells express the CD34 antigen in a diffuse cell surface pattern with some concentration on microvilli. Expression is downregulated with proliferation in continuous culture and undetectable after nine population doublings but can be maintained by restraining cell proliferation and promoting cell contact. Expression of CD34 at the antigen and mRNA levels on early passage cells is rapidly downregulated by interleukin-1 beta (IL-1 beta), interferon-gamma (INF-gamma), and tumor necrosis factor-alpha (TNF-alpha) under conditions in which these ligands upregulate the adhesion molecules: endothelial leukocyte adhesion molecule 1 (ELAM-1) and intracellular adhesion molecule 1 (ICAM-1). This reciprocal pattern of expression and the topographic distribution of CD34 molecules on the lumenal interdigitated microprocesses of adjacent endothelial cells in vivo suggest that CD34 might have a negative modulating role on adhesion functions of endothelia.

Sixty-four samples of urethral cells from male sexual partners of women with genital human papillomavirus (HPV) infection were analyzed for the presence of HPV types 6, 11, 16, and 18 by polymerase chain reaction (PCR) followed by slot blot hybridization. Additional samples from 37 of these subjects were analyzed for the presence of viral cytopathic effects by conventional cytology. By PCR, HPV DNA was detected in 21% (14/64) of samples. By cytology, 16% (6/37) of the samples showed cellular changes consistent with HPV infection. Polymerase chain reaction and cytology results were concordant for presence and absence of HPV in 5 and 28 cases, respectively. Three additional HPV-positive cases were obtained with PCR in the cytologically negative samples. The cytologic abnormalities were found to be associated with the presence of both low-risk HPV types and meatal acetoreactivity. On the contrary, HPV DNA positivity by PCR was unrelated to viral type and peniscopic findings. Urethral HPV infection was detected by PCR in 30% of males with visible penile lesions and in 18% of those without. These results indicate that PCR analysis of urethral samples is a helpful adjunct to cytology for the detection of HPV DNA in absence of cytologic evidence of infection.

The present study provides immunobiochemical and molecular data on the differentiation-linked expression of the bcl-2 proto-oncogene in normal and neoplastic myeloid cells. Using a recently developed monoclonal antibody (MoAb) to the bcl-2 molecule, staining of normal bone marrow myeloblasts, promyelocytes, and myelocytes, but neither monocytes nor most polymorphonuclear cells, was demonstrated. By two-color flow cytometric analysis, bcl-2 was evidenced in CD33+ and CD33+/CD34+ myeloid cells as well as in the more primitive CD33-/CD34+ population. The leukemic cell lines HL-60, KG1, GM-1, and K562 were bcl-2 positive together with 11 of 14 acute myeloid leukemias (AML) and three of three chronic myeloid leukemias (CML) in blast crises; six of seven CML were negative. Among myelodysplastic cases, augmentation of the bcl-2 positive myeloblastic compartment was found in refractory anemia with excess of blasts (RAEB) and in transformation (RAEB-t). Western blots of myeloid leukemias and control lymphocytes extracts evidenced an anti-bcl-2 immunoreactive band of the expected size (26 Kd). Moreover, the HL-60 and KG1 cell lines, both positive for the bcl-2 protein, exhibited the appropriate size bcl-2 mRNA (7.5 Kb). These findings clearly indicate that the bcl-2 gene is operative in myeloid cells and that the anti-bcl-2 MoAb identifies its product and not a cross-reactive epitope. Induction of HL-60 differentiation toward the monocytic and granulocytic pathways was accompanied by a marked decrease in bcl-2 mRNA and protein levels; bivariate flow cytometric analysis showed that the fraction becoming bcl-2 negative was in the G1 phase of the cell cycle. These data establish that the bcl-2 proto-oncogene is expressed on myeloid cells and their progenitors and is regulated in a differentiation-linked manner.

The role of protein glycosylation in the tumor lysis mediated by effector cells derived from Moloney-sarcoma-virus(MSV)-immune mice was studied. Treatment of the Moloney-virus-induced H-2b lymphoma target cells, MBL-2, with tunicamycin (TM), an inhibitor of the protein-N-linked glycosilation, was found to cause a loss of susceptibility to lysis by MSV-immune syngeneic effectors cells, while the same target cells remained fully sensitive to the lytic action of anti-H-2b-immune lymphocytes. Examination of MBL-2 cell surface by lactoperoxidase, 125I iodination, and immunoprecipitation by antiviral protein sera revealed that env but not gag viral gene-encoded products were expressed on the surface of this lymphoma. The TM-induced alteration of cell surface expression of H-2Db, H-2Kb, and gp70 antigens was examined by a combined approach of serological and biochemical techniques. The results were concordant in indicating that (1) after 16 h of TM treatment the cells showed a decreased expression of the three glycoproteins, (2) H-2Db (the restriction element in this system) resulted more affected by the treatment than its counterpart H-2Kb (75% vs 50% reduction as compared to untreated cells), (3) an additional lighter form of H-2Kb was found on the surface of TM-treated cells. In the context of an "associative recognition' of Db and gp70 by MSV-immune effector cells, our results may explain the loss of susceptibility to antitumor effectors of TM-treated MBL-2 cells by a quantitative reduction in the expression of both molecules which interact to create the target structure of syngeneic effectors.

Plasma membrane preparations were obtained from solid lymphosarcomas and fibrosarcomas by disrupting the tissues with a mechanical press. The subcellular fractions were isolated by differential centrifugations and examined by electron microscopy. The membrane-enriched fractions were also assayed for protein content and analyzed in SDS-polyacrylamide gel electrophoresis; a fairly good reproducibiltiy was found comparing different membrane preparations derived from the same tumor. The H-2 antigenic activity of the different membrane preparations was demonstrated in vitro by the inhibition of the C'-dependent 51Cr-release assay using monospecific H-2 alloantisera. The specificity of the assay was ascertained by the lack of inhibition of unrelated monospecific H-2 alloantisera and by a dose-response relationship between the amount of added membranes and the observed inhibition. The immunogenicity of the membranes was assessed in vivo by immunizing allogeneic mice that developed anti-H-2 alloantibodies. The possible mechanisms of the tissue disruption by the press are also discussed.