Skin Toxicity in Early Breast Cancer Patients Treated with Field-In-Field Breast Intensity-Modulated Radiotherapy versus Helical Inverse Breast Intensity-Modulated Radiotherapy: Results of a Phase III Randomised Controlled Trial.

AIMS: Skin toxicity is a common adverse effect of breast radiotherapy. We investigated whether inverse-planned intensity-modulated radiotherapy (IMRT) would reduce the incidence of skin toxicity compared with forward field-in-field breast IMRT (FiF-IMRT) in early stage breast cancer. MATERIALS AND METHODS: This phase III randomised controlled trial compared whole-breast irradiation with either FiF-IMRT or helical tomotherapy IMRT (HT-IMRT), with skin toxicity as the primary end point. Patients received 50 Gy in 25 fractions and were assessed to compare skin toxicity between treatment arms. RESULTS: In total, 177 patients were available for assessment and the median follow-up was 73.1 months. Inverse IMRT achieved more homogeneous coverage than FiF-IMRT; erythema and moist desquamation were higher with FiF-IMRT compared with HT-IMRT (61% versus 34%; P < 0.001; 33% versus 11%; P < 0.001, respectively). Multivariate analysis showed large breast volume, FiF-IMRT and chemotherapy were independent factors associated with worse acute toxicity. There was no difference between treatment arms in the incidence of late toxicities. The 5-year recurrence-free survival was 96.3% for both FiF-IMRT and HT-IMRT and the 5-year overall survival was 96.3% for FiF-IMRT and 97.4% for HT-IMRT. CONCLUSIONS: Our study showed significant reduction in acute skin toxicity using HT-IMRT compared with FiF-IMRT, without significant reduction in late skin toxicities. On the basis of these findings, inverse-planned IMRT could be used in routine practice for whole-breast irradiation with careful plan optimisation to achieve the required dose constraints for organs at risk.

The interactome of metabolic enzyme carbonic anhydrase IX reveals novel roles in tumor cell migration and invadopodia/MMP14-mediated invasion.

Carbonic anhydrase IX (CAIX) is a hypoxia inducible factor 1-induced, cell surface pH regulating enzyme with an established role in tumor progression and clinical outcome. However, the molecular basis of CAIX-mediated tumor progression remains unclear. Here, we have utilized proximity dependent biotinylation (BioID) to map the CAIX 'interactome' in breast cancer cells in order to identify physiologically relevant CAIX-associating proteins with potential roles in tumor progression. High confidence proteins identified include metabolic transporters, ß1 integrins, integrin-associated protein CD98hc and matrix metalloprotease 14 (MMP14). Biochemical studies validate the association of CAIX with α2ß1 integrin, CD98hc and MMP14, and immunofluorescence microscopy demonstrates colocalization of CAIX with α2ß1 integrin and MMP14 in F-actin/cofilin-positive lamellipodia/pseudopodia, and with MMP14 to cortactin/Tks5-positive invadopodia. Modulation of CAIX expression and activity results in significant changes in cell migration, collagen degradation and invasion. Mechanistically, we demonstrate that CAIX associates with MMP14 through potential phosphorylation residues within its intracellular domain, and that CAIX enhances MMP14-mediated collagen degradation by directly contributing hydrogen ions required for MMP14 catalytic activity. These findings establish hypoxia-induced CAIX as a novel metabolic component of cellular migration and invasion structures, and provide new mechanistic insights into its role in tumor cell biology.

Targeting carbonic anhydrase IX depletes breast cancer stem cells within the hypoxic niche.

The sub-population of tumor cells termed 'cancer stem cells' (CSCs) possess the capability to generate tumors, undergo epithelial-mesenchymal transition (EMT) and are implicated in metastasis, making treatments to specifically target CSCs an attractive therapeutic strategy. Tumor hypoxia plays a key role in regulating EMT and cancer stem cell function. Carbonic anhydrase IX (CAIX) is a hypoxia-inducible protein that regulates cellular pH to promote cancer cell survival and invasion in hypoxic microenvironments and is a biomarker of poor prognosis for breast cancer metastasis and survival. Here, we demonstrate that inhibition of CAIX expression or activity with novel small-molecule inhibitors in breast cancer cell lines, or in primary metastatic breast cancer cells, results in the inhibition of breast CSC expansion in hypoxia. We identify the mTORC1 axis as a critical pathway downstream of CAIX in the regulation of cancer stem cell function. CAIX is also required for expression of EMT markers and regulators, as well as drivers of 'stemness', such as Notch1 and Jagged1 in isolated CSCs. In addition, treatment of mice bearing orthotopic breast tumors with CAIX-specific small-molecule inhibitors results in significant depletion of CSCs within these tumors. Furthermore, combination treatment with paclitaxel results in enhanced tumor growth delay and eradication of lung metastases. These data demonstrate that CAIX is a critical mediator of the expansion of breast CSCs in hypoxic niches by sustaining the mesenchymal and 'stemness' phenotypes of these cells, making CAIX an important therapeutic target for selectively depleting breast CSCs.

An analysis of the impact of pathology review in gynecologic cancer.

PURPOSE: To analyze the impact of pathology review in gynecologic malignancies. METHODS AND MATERIALS: For all new gynecologic patients seen between December 2, 1993 and January 4, 1996, we conducted a retrospective chart review to determine if a pathology review by the institute's consultant pathologist changed the diagnosis, and if so whether the change altered patient management. A total of 514 patients were seen, of whom 120 had cervical cancer, 226 had endometrial cancer, 122 had a primary ovarian or peritoneal malignancy, 9 had a vaginal malignancy, 28 had vulvar cancer, and 9 had a miscellaneous gynecologic malignancy. RESULTS: On pathology review the diagnosis changed for 200 of 599 specimens (33%). This altered management for 63 of 514 patients (12%). For patients with cervical cancer, the grade of tumor was the main change in pathologic diagnosis, with occasional change in the presence of lymph vascular invasion. These did not translate into patient management alterations. Eight patients (1.5%) had management alterations. The changes in depth of invasion and vascular invasion altered management for 3 patients. Changes in pap smears resulted in two management alterations, and changes in histologic diagnoses altered management for 3 cases. For endometrial primaries the changes in pathologic diagnosis included grade, depth of invasion, and the presence of cervical involvement. This did alter management in 40 cases (8%). For the ovarian malignancies, the main changes were grade, extent of disease, or histologic classification, some of which (10 patients, 2%) resulted in altered management. One patient with a vaginal lesion had the diagnosis changed, which did alter management. Of the patients diagnosed with vulvar cancer, the pathologic diagnosis changed for 11 patients. This included changes in grade and depth of invasion. This altered management of 2 patients. The remaining miscellaneous gynecologic malignancies had only two diagnosis changes that altered management. CONCLUSIONS: Pathologic review of gynecologic malignancies is justified as it can alter patient management. In addition, the process facilitates cooperation of the multidisciplinary team and provides a valuable educational forum to enhance patient care.

Legal obligation of physicians to disclose information to patients.

Obtaining a patient's consent is a routine daily process for physicians, although many are unaware of the scope of this legal obligation. In 1980 the Supreme Court of Canada changed the law relating to informed consent; promotion of patient autonomy shifted the focus from a standard of professional disclosure to one of a "reasonable patient." Physicians have a legal obligation to disclose to patients specific information, the scope of which is determined by a court on the basis of a reasonable patient's expectation and the circumstances of the case. This gives rise to many controversies in the practice of clinical medicine. It is difficult for physicians to know which treatment risks require disclosure, since this is decided by a court in a retrospective analysis of the evidence. Will the court recognize exceptions to the duty of disclosing information? If several health care professionals are involved in a patient's care who has the duty to disclose information? Can this duty be delegated? This paper provides physicians with guidelines that are consistent with the promotion of patient autonomy and comply with the doctrine of informed consent. In addition, it suggests ways of improving awareness of the doctrine and procedures to ease its application.

Effects of environmental changes on sugars, tannins, and organized growth in cell suspension cultures of white spruce.

Callus from hypocotyls of white spruce (Picea glauca [Moench] Voss) was grown on agar under defined conditions with high levels of calcium nitrate. Transfer of callus to liquid suspension cultures and maintenance of suspensions either under a regime of constant temperature and light or under alternating conditions similar to those of a late spring day, affected the content of free sugars, tannins, and aldehydes. Under the alternating conditions the levels of these substances increased greatly compared to those under the constant environment. By contrast, vascularization of cell clumps, which was comparable to the differentiation of hypocotyls in seedlings, was obtained only under constant conditions. Cells at the centre of the clumps developed secondary wall thickenings and bordered pits, and were surrounded by cambial-like initials.

Tannin inclusions in cell suspension cultures of white spruce.

Tannins were detected cytochemically in cell suspension cultures of white spruce (Picea glauca [Moench] Voss) and were studied by electron microscopy. Tannin inclusions originated within cytoplasmic vacuoles, possibly derived from the endoplasmic reticulum, and accumulated in the central vacuole through enlargement and coalescence of those cytoplasmic vacuoles. Structural information supported the suggested metabolic relationship between starch and tannin, although tannins did not develop within plastids. Membranous material, resembling myelinlike bodies, was often observed in close association with tannins.

Fine structural observations on the epidermis : II. the cuticle.

In species of Apium, Eryngium and Humulus, the cuticular membrane of the petiole could be resolved into two parts, of which the inner one appeared amorphous and after staining appeared to be penetrated by an electron-dense reticulum, whereas the outer layer showed a lamellate structure consisting of electron-dense and electron-transparent plates, 50-80 Å in thickness. These layers are considered to correspond with the cuticular layer and the cuticle proper, respectively. In species of Abutilon and Rumex the cuticle proper did not exhibit the lamellate structure. In the leaves of Eryngium the outer lamellated structure was present in the cuticle of both young and mature leaves. Both the lamellate and non-lamellate types of the cuticle proper increased in thickness with age of the specimen. The results are discussed in relation to earlier investigations.

Fine structural observations on the epidermis : I. The epidermal cell wall.

The organization of the wall of epidermal cells in the petiole of species of Apium, Eryngium, Rumex, and Abutilon as well as that of the epidermis of Avena coleoptile has been investigated. The outer and inner tangential walls consist of layers in which the cellulose microfibrils are oriented alternately parallel or transverse to the longitudinal cell axis. This organization resembles that previously described for collenchyma cell walls (Wardrop, 1969; Chafe, 1970). On the radial (anticlinal) walls the orientation of the microfibrils is transverse and these appear continuous with the layers of transverse orientation of the outer and inner tangential walls. Variation in thickness of the outer tangential, and radial, and inner tangential walls appears to result from the variation in thickness of those layers in which the microfibrils have a longitudinal orientation. The extent to which these observations can interpreted in terms of some type of modified "multi-net" growth is discussed.

Microfibril orientation in plant cell walls.

The distribution of particles on the surface of the plasmalemma in the collenchyma of Apium graveolens was studied by the freeze-etching technique. The aim was to determine whether the distribution of particles was related to the known longitudinal or transverse orientation of cellulose microfibrils in different layers of the walls of these cells. Preliminary statistical studies have shown no obvious correlation between particle distribution and microfibril orientation although the distribution appeared uniform rather than random. Qualitatively, the particle distribution on the plasmalemma of differentiating xylem fibres of Eucalyptus maculata and of the cortical parenchyma of Avena sativa coleoptiles appeared to be similar to that observed on the plasmalemma of Apium. No correlation between the particle distribution and the microfibril orientation known to exist in the walls of these cells could be discerned.The orientation of microtubules in the cytoplasm of collenchyma cells of Apium graveolens was parallel to the microfibril orientation in many instances, but exceptions were noted. A possible interpretation for this variation is discussed. It is concluded that the microtubules are the structures which are most likely to be involved in determining microfibril orientation in the cell wall.

The fine structure of the collenchyma cell wall.

An investigation of the fine structure of the cell wall was carried out on representative species of four morphological forms of collenchyma, viz. annular, angular, plate and lacunate. In all forms lamellae were observed in which the orientation of cellulose microfibrills was transverse. These lamellae alternated throughout the thickness of the wall with lamellae in which the orientation of cellulose microfibrils was longitudinal. The distribution of pectic substances within the wall, when stained with ruthenium red and by the alkaline hydroxylamine-ferric chloride method of Reeve (1958), was generally not observed in lamellate form although instances of lamellae with high pectic content were observed.