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Aim: To evaluate the relationship between malignant appearance of mammographic calcification and breast cancer pathological features, and to explore the predictive value of calcification appearances and morphology changes in neo-adjuvant setting. Methods: 419 patients with operable breast cancer received neo-adjuvant therapy between 2008.2 and 2011.8 in Shanghai Cancer Hospital. Core needle biopsy was conducted before preoperative therapy to determine cancer and achieve pathological features. Mammogram (MG), ultrasound and breast MRI were routinely done prior to therapy and prior to surgical operation. We conducted a detailed analysis of MG images in patients with malignant calcification, recorded the morphology, distribution, range, density, diameter and number of the calcification. Results: 419 patients enrolled, 108 patients (25.8%) showed malignant calcification in MG, 6 patients missed the first MG before therapy. 214 patients were Luminal A, 95 were Luminal B, 64 were Her2 positive and 46 were triple negative, the pCR rate was 14%, 30.5%, 53%, 43.5% respectively. Patients with malignant calcification have more ER positive (81.5% vs. 71.7%, p = 0.045) and HER2 positive (51.8% vs. 33%, p = 0.001) diseases. The pCR rate was 26% in patients with malignant calcification and 28% in patients without, p = 0.8. Different morphology shapes showed similar pCR rate, p = 0.89. Casting-type had a higher pCR rate 45.8%, compared with 20% in crushed stone-like and 16.7% in powderish, p = 0.031. Range more than 5cm had a higher pCR rate, 40.7% vs. 20%, p = 0.034. Density, diameter and number of the calcification did not reach statistical difference, however high density, diameter >1mm and number >20 per cm² showed a trend of higher pCR rate. Patients with diameter ≤0.5mm had a higher lymphatic vascular invasive rate 51.4%, compared to diameter≤1mm (26.8%) and diameter >1mm (22.7%), p = 0.03. Morphology and distribution of calcification did not change obviously. Less than 30% patients showed changes in range, number or density, no relationship with pCR rate. Conclusion: Patients with malignant calcification are more likely to have ER positive and Her2 positive diseases. MG should be considered the standard prior to the start of therapy, the distribution and range of the calcification may predict pCR rate. Calcification appearance does not change significantly after neo-adjuvant therapy, therefore MG is not an appropriate method for efficacy evaluation. But MG before surgery is still useful to identify the extent of surgery, especially in breast conserve therapy. [ABSTRACT FROM AUTHOR]

An estrogen receptor-driven, multistep process for estrogen carcinogenesis in the Syrian hamster kidney is proposed. Because in this species the reproductive and urogenital tracts arise from the same embryonic germinal ridge, it is evident that the kidney has carried over genes that are responsive to estrogens. Using in situ hybridization, overexpression of early estrogen-response genes, i.e., c-myc and c-fos, has been shown to be localized preferentially in early renal tumor foci after 3.5-4.0 months of estrogen treatment. This event coincides with an increased number of S-phase proliferating cell nuclear antigen-labeled cells in these tumor foci, along with a rapid rise in aneuploid frequency in the kidney. Western blot analyses of c-MYC and c-FOS protein products support the overexpression of these genes. Amplification of c-myc, 2.4-3.6-fold, but not of c-fos, was detected in 67% of the primary renal tumors examined, by Southern blot analyses. Consistent chromosomal gains, common to both diethylstilbestrol- and estradiol-induced renal neoplasms, were observed in chromosomes 1, 2, 3, (6), 11, (13), 16, 20, and 21 (chromosome number alterations are indicated in parentheses). Using fluorescence in situ hybridization, the c-myc gene was localized to hamster chromosome 6qb. Chromosome 6 exhibited a high frequency of trisomies and tetrasomies in the kidney after 5.0 months of estrogen treatment and in primary renal tumors. The data presented indicate that estrogen-induced genomic instability may be a key element in carcinogenic processes induced by estrogens.

Cross-coupling of active protein-1 (AP-1) and nuclear factor (NF)-kappaB has been reported. In the present study, we investigated the possibility that both of these two transcription factors might contribute to the process of tumor promoter-induced transformation. To establish a stable reporter cell system, two reporter genes were stably transfected into a JB6 mouse tumor promotion-sensitive (P+) cell line: a luciferase reporter controlled by a collagenase AP-1 sequence and a chloramphenicol acetyltransferase reporter controlled by an interleukin 6 NF-kappaB sequence. This double-reporter cell line maintained the phenotype of tumor promotion sensitivity and was able to report basal or induced AP-1 and NF-kappaB transactivation. The cytokine tumor promoter tumor necrosis factor (TNF)-alpha transactivated NF-kappaB and AP-1 for both DNA binding and transcriptional activity. Pyrrolidine dithiocarbamate, an antioxidant that acts as an NF-kappaB inhibitor, efficiently inhibited 12-O-tetradecanoylphorbol-13-acetate (TPA) or TNF-alpha induced NF-kappaB as well as AP-1 transactivation and cell transformation, suggesting dependency of transformation on both transcription factors. The AP-1 transrepressing-retinoid SR11302 transrepressed AP-1 and cell transformation when these were TPA induced but not when TNF-alpha induced, indicating different signaling pathways for TNF-alpha and TPA. Supershift electrophoresis mobility shift assay revealed that Jun B and c-Jun were absent from the AP-1/DNA complex following TNF-alpha but present following TPA treatment. Together, these results suggest that both AP-1 and NF-kappaB activation may be required for transformation whether induced by TPA or by TNF, and the differential sensitivity of TPA and TNF-alpha-induced transformation to inhibition by a retinoid might be explained by differences in the composition of the DNA-bound AP-1 complexes.

Human breast cancer cells (MCF-7) overexpressing manganese-containing superoxide dismutase (MnSOD) by stable or transient transfection were challenged with the cytotoxicity of tumor necrosis factor alpha (TNF-alpha), hyperthermia, and a combination of both. In contrast to the vector control and wild-type MCF-7 cells, the stable MnSOD transfectants showed significant resistance to the cytotoxicity of TNF-alpha (100 units/ml), heat at 43 or 45 degrees C, and a combination of TNF-alpha and heat at 43 degrees C. To probe the correlation of MnSOD levels with cell survival, cell sensitivity to TNF-alpha, heat at 43 degrees C, or a combination of both was also measured after MnSOD cDNA transient transfection. The data showed that the level of cell resistance was proportional to the exogenous MnSOD gene expression. These results suggest that superoxide free radicals or their reaction products are responsible for much of the synergistic cytotoxicity of TNF-alpha and hyperthermia.

Chronic administration of estrogen to male Syrian hamsters for 7.0 to 9.0 months induces a high frequency of estrogen-dependent renal cancers. We have proposed a sequential multistage scheme involving tubular cell damage, regenerative cell proliferation, aneuploidy, chromosomal imbalance, genetic instability, gene alteration, and amplification as essential steps for estrogen carcinogenesis in this model. A systematic study was undertaken to assess the expression of nuclear proto-oncogenes, c-myc, c-fos, and c-jun, and suppressor genes, p53 and WT-1, by Northern blot analysis to further support this scheme. Hamster kidney RNA, taken at monthly intervals (1.0 to 6.0 months) from diethylstilbestrol (DES)-treated castrated male hamsters and corresponding age-matched untreated controls was used in these studies, as well as primary estrogen-induced renal tumor RNA, for reference. Although no significant changes in the expression of these proto-oncogenes were detected in the first 4 months of estrogen treatment relative to age-matched controls, 2.1-kb c-myc expression was elevated 2.8- and 4.1-fold at 5.0 and 6.0 months, respectively. Moreover, the expression of 2.2-kb c-fos transcript rose 4.6- and 4.8-fold; and 3.2- and 2.7-kb c-jun expression increased 2.8- and 5.1-fold at these same respective estrogen treatment time intervals. Tumor suppressor gene expression, p53 and WT-1, was also evaluated in similar estrogen-exposed hamsters. Although no significant changes were found in hamster kidney p53 expression in the first 5.0 months of DES treatment, it rose 1.8-fold at 6.0 months of estrogen treatment and more than 2.0-fold in the primary renal tumor. In contrast, no detectable changes in WT-1 expression were found during the first 6.0 months of DES treatment. However, a dramatic 7.0-fold increase in WT-1 expression was observed in the primary renal tumor. It is evident that two WT-1 transcripts reside in the hamster kidney; a lower molecular weight transcript was found in the normal adult kidney, and a higher molecular weight 3.2-kb transcript was observed in the renal tumor, similar to that seen in the newborn mouse kidney. In summary, the estrogen-induced inappropriate gene expression, including p53, reported herein, is consistent with the view that the elevations seen in gene expression contribute to proliferative advantages of certain proximal tubular interstitial cells necessary for estrogen-driven tumor formation in the hamster.

Both retinoic acid (RA) treatment and dominant-negative c-Jun mutant expression effectively inhibit phorbol ester-induced AP-1 activity and induced neoplastic transformation in mouse epidermal JB6 cells. However, both reagents also target non-AP-1 molecules in addition. Because liganded retinoic acid receptors interact with and transactivate RA response elements (RAREs) on DNA, as well as interact with Jun protein to block AP-1 activity, the question arises as to which of these two activities of retinoids is responsible for antitumor-promoting activity. To address this question we generated JB6 promotion-sensitive (P+) cell lines that are stably transfected with a construct containing the collagenase promoter bearing one AP-1-binding site that drives a luciferase reporter gene. The stable collagenase-luciferase-transfected cell lines showed 1.5-3.5-fold enhanced AP-1 activity when treated with 12-0-tetradecanoyl-phorbol-13-acetate (TPA). Up to 90% of TPA-induced AP-1 activity was blocked by retinoids SR11238, SR11302, or trans-RA, but not by retinoid SR11235. Of these retinoids, only RA and SR11235 were able to transactivate RARE-dependent gene expression. Transrepression of TPA-induced AP-1 and transactivation of RARE by RA, SR11238, and SR11302 were concentration dependent at 10(-10) to 10(-6) M retinoid. When tested for activity in inhibiting tumor promoter-induced transformation in JB6 P+ cells, the retinoids specific for AP-1 transrepression were inhibitory, whereas SR11235, which only activated RARE, showed little effect. We thus conclude that the AP-1-blocking activity of retinoids is likely to be responsible for the antitumor-promoting activity. This result, together with the observation that dominant-negative Jun blocks transformation, argues for a requirement of induced AP-1 in the tumor promoter-induced transformation process.

The therapeutic use of estrogens has been associated with an increased risk of some of the most predominant, as well as less prevalent, cancers in women. The estrogen-induced renal tumor is one of the primary animal models to evaluate the carcinogenic properties of estrogens. Correlations were made with various estrogens by using parameters of estrogenicity end points such as competitive binding, progesterone receptor induction, and alterations in prolactin levels; in vitro renal proximal cell proliferation; and in vivo estrogen-induced carcinogenicity. The most potent estrogens were Moxestrol (MOX), diethylstilbestrol (DES), and 17 beta-estradiol, followed by indenestrol B, 16 alpha-hydroxyestrone, and 11 beta-methoxyestradiol with moderate estrogenic activities, whereas 11 beta-methylestradiol, 17 alpha-estradiol, indanestrol, and deoxoestrone were all relatively weaker. As expected, hydrolyzed Premarin (unconjugated estrogens) was strongly estrogenic. Of the estrogens tested, MOX was the most potent carcinogenic estrogen in the hamster kidney. Both 16 alpha-hydroxyestrone and 11 beta-methoxyestradiol induced intermediate tumor incidences with distinctly lower frequencies of renal tumor foci compared to the most potent carcinogenic estrogens. However, hamsters treated for 9.0 months with 11 beta-methylestradiol, 17 alpha-estradiol, deoxoestrone, and indanestrol exhibited no tumors. In contrast, treatment with estrone, equilin plus d-equilenin, and hydrolyzed Premarin for the same time period resulted in 100% renal tumor incidences and numerous tumor foci. Cell proliferation studies of cultured hamster kidney proximal tubule cells were carried out at varying estrogen concentrations (0.01-100 nM). Exposure to MOX resulted in consistently high renal cell proliferative response over a concentration range of 0.1-10 nM. Strongly carcinogenic estrogens such as estrone had a maximal renal cell proliferation response (2.4-fold above untreated control levels) between 0.1 and 10 nM, DES and 17 beta-estradiol responded at 1.0 nM, and 4-hydroxyestradiol responded at 10 nM. Interestingly, exposure to ethinylestradiol, a potent estrogen, at similar or higher doses as those used for DES and 17 beta-estradiol, yielded only a 10% renal tumor incidence and induced only a 1.7-fold increase in proximal tubule cell proliferation. In contrast, 17 alpha-estradiol, deoxoestrone, indanestrol, and 11 beta-methylestradiol, all weakly estrogenic and noncarcinogenic agents, had relatively little effect on tubule cell proliferation. The hydrolyzed Premarin exhibited a maximal 2.0-fold cell proliferative response at 10 nM. The present results provide clear evidence that, in the hamster kidney, the degree of carcinogenicity of a given estrogen correlates with its ability to induce proximal tubule cell proliferation in vitro.(ABSTRACT TRUNCATED AT 400 WORDS)

Syrian hamsters were treated with diethylstilbestrol (DES), a potent estrogen and kidney carcinogen, or ethinyl estradiol (EE), a strong estrogen but weak carcinogen, for 1-9 months. At monthly intervals their kidneys were studied using light, immunoperoxidase, and electron microscopic techniques. At 5 months, DES-treated animals exhibited interstitial lesions composed of small round cells with a high nuclear:cytoplasmic ratio. Immunoperoxidase and ultrastructural studies showed these cells to be similar to cells in fully formed tumors at 9 months. Early lesions in EE-treated animals (seen as early as 1 month) were dissimilar, these lesions appeared in the deep cortex adjacent to the renal pelvis, where proximal tubules underwent hyperplastic changes, showing columnar cells with large nuclei, occasional mitoses, and sloughing of apical cytoplasm. Cells in early lesions of EE-treated animals did not resemble the fully developed tumor in either immunoperoxidase or ultrastructural features; although with longer treatment these tubular lesions progressed to dysplasia (3-5 months) and severe dysplasia/carcinoma in situ (7 months), they did not form grossly visible tumors during the 9-month study. Both early lesions identified were specific, inasmuch as they were not observed in control animals and animals treated with beta-dienestrol and 17 alpha-estradiol (noncarcinogenic weak estrogens). Animals given a combination of DES and EE showed tubular hyperplasia but not interstitial lesions; this finding was of particular interest because hamsters given this combination of estrogens do not develop gross renal tumors. These results strongly implicate the primitive interstitial cell in the hamster kidney as the cell of origin of the DES-induced neoplasm.

The influence of alpha-naphthoflavone (ANF) on the metabolism and binding of radiolabeled ethinylestradiol (EE2) has been examined both in vitro and in vivo in hamster liver microsomes. [14C]EE2 was metabolized extensively to seven major oxidative metabolites, 7 alpha-hydroxyEE2, 4-hydroxyEE2, 2-hydroxyEE2, D-homoestrone, monohydroxyEE2, and two dihydroxyEE2 metabolites identified as catechols with the additional hydroxy group on ring B or C, and a nonpolar fraction. The main EE2 metabolite found was 2-hydroxyEE2, and it represented 47% of the total metabolites formed. The total amount of EE2 catechol metabolites formed in untreated hamster liver microsomes was 65.5%. When ANF was added in vitro to these hepatic microsomes, there was a 27-45% decline in 2-hydroxyEE2 formation, a 98% reduction in dihydroxyEE2 (catechol-2), and a 56-66% reduction in the nonpolar fraction. The marked inhibition of EE2 metabolism by the in vitro addition of ANF is reflected by a corresponding decrease in the irreversible binding of radioactive hormone to hamster liver microsomal proteins. In contrast, a biphasic response of ANF on EE2 metabolism was observed after in vivo administration for 2.0 and 4.0 months. After 2.0 months of ANF treatment, there was a modest decline in all [14C]EE2 metabolites, except 2-hydroxyEE2 and dihydroxyEE2 (catechol 1). After 4.0 months of ANF treatment, the reduction in EE2 metabolism was even lower than after 2.0 months of treatment. Most interestingly, there was a 1.5-fold increase in 2-hydroxyEE2 after 4.0 months of ANF treatment, representing nearly 69% of the total EE2 metabolites formed. These results are consistent with an increase in irreversible binding of [14C]EE2 metabolites to hamster liver microsomal proteins after 4.0 months of ANF treatment. The relative 1.3-fold and the absolute 1.5-fold increases in 2-hydroxyEE2 after 2.0 and 4.0 months of ANF treatment in vivo, respectively, suggest that the elevation in this reactive EE2 metabolite precursor may contribute importantly to hepatotumorigenesis in the hamster following prolonged EE2 plus ANF treatment.

The estrogen-induced hamster renal carcinoma contains appreciable amounts of all cytosolic steroid receptor classes sedimenting as 7 to 8S moieties following sucrose gradient centrifugation. Their relative concentrations, expressed in fmol/mg protein +/- S.E. are progesterone (1496 +/- 23) greater than estradiol (218 +/- 3) greater than 5 alpha-dihydrotestosterone (154 +/- 7) greater than dexamethasone (138 +/- 3) greater than aldosterone (40 +/- 2). No cross-competition is apparent for either estrogen or progesterone receptors, but progesterone competes for both androgen and adrenocorticoid binding. These hormone-receptor complexes undergo nuclear translocation using purified tumor nuclei and in tissue minces at elevated temperatures. Salt-extractable nuclear receptors for estrogen (5S), androgen (3.2S), progesterone (2.7S), and corticosteroid (3.5S) have been identified. The existence of five specific steroid receptors within a single tissue is unique and provides a novel model for studying the interrelated actions of all steroid hormones and their therapeutic responses in a hormone-dependent neoplasm.

Both synthetic and natural estrogens have been studied for their ability to induce renal carcinomas in castrated male hamsters after 9.0 months of treatment. Tumor foci were detected in frozen serial sections stained histochemically for estrase activity. Both diethylstilbestrol (DES) and 17 beta-estradiol had equal ability (100%) to induce renal tumors [approximately 20.5 +/- 3 (S.E.) tumor foci] in these animals. Hexestrol induced the same incidence and number of renal carcinoma foci as DES or 17 beta-estradiol. However, alpha -dienestrol and DES 3,4-oxide showed an 86 to 88% incidence of renal tumors in hamsters (approximately 10.8 +/- 3). When equilin and d-equilenin, components of therapeutic conjugated estrogens, were tested, only equilin had a 76% incidence of renal tumor foci (5.5 +/- 0.9). The ability of these stilbene and steroidal estrogens to compete for renal tumor estrogen receptor generally correlated well with their ability to cause renal tumorigenesis in the hamster with one notable exception. Although ethinyl estradiol competed as well as did DES or 17 beta-estradiol for estrogen receptor, had similar ability to induce renal progesterone receptor, and led to similar high serum prolactin levels as either DES or 17 beta-estradiol, it had only weak carcinogenic activity (21%) in the hamster kidney (0.6 +/- 0.5 foci). These data represent the first detailed analysis of the relative carcinogenic activity of different estrogens within a given tumor-inducing system, and based on the carcinogenicity data of hexestrol and alpha-dienestrol presented herein, they suggest that epoxidation of the olefinic double bond and the p-quinone metabolite of DES probably are not involved significantly in its carcinogenic activity. Moreover, the poor carcinogenic activity of ethinyl estradiol in this system, despite strong estrogenicity, suggests that estronic activity alone may not be sufficient to effect renal tumorigenesis in the hamster.

Estrogen 2- and 4-hydroxylase (ESH), a microsomal enzyme which mediates the formation of catechol estrogens, has been studied in the kidneys of castrated male Syrian hamsters, a species uniquely susceptible to induction of renal carcinomas by both steroidal and stilbene estrogens. The apparent Km for estrone was 17.0 microM, and Vmax was 0.5 pmol per mg protein per min for ESH in renal microsomes derived from castrated hamsters. Different steroidal estrogen substrates exhibited decreasing catechol formation with hamster kidney microsomal preparations in the following order: estrone greater than d-equilenin greater than 17 beta-estradiol greater than equilin greater than ethynyl estradiol greater than estriol. Except for beta-dienestrol, the stilbene estrogens revealed levels of catechol formation that were similar to 17 beta-estradiol. These findings provide a rationale for the weak carcinogenic activity of ethynyl estradiol, estriol, and beta-dienestrol, since they were poor substrates for hamster renal ESH and for the relatively potent carcinogenic activity of the distal metabolite of diethylstilbestrol, indenestrol B/A, which exhibited substantial levels of o-hydroxylation when used as a substrate. Interestingly, ESH activity was significantly greater in the hamster kidney compared to corresponding rat tissue, and catechol estrogen formation was found to be 2.5- to 19-fold higher in the hamster kidney compared to the rat, using various steroidal and stilbene estrogen substrates. Moreover, the finding that a 3.5- to nearly 6-fold decrease, compared to untreated levels, in catechol formation in kidneys but not in livers of alpha-naphthoflavone-exposed hamsters, depending on the steroidal or stilbene estrogen substrate used, is consistent with the belief that the catechol estrogen pathway is pertinent to events leading to estrogen-induced renal tumorigenesis in the hamster.

Linear sucrose gradient analyses reveal that all estrogen-induced and -dependent primary renal tumor cytosols examined contain an 8 S and variable amounts of 4 S receptor in low ionic buffer concentrations. Similar results were obtained with extracts of primary metastases of these tumors. Sucrose gradients containing high salt (0.4 M KCl) convert the 8 S receptor in both the hamster renal tumor and uterus to a 4 to 5 S complex. Scatchard plot analysis reveals that the renal tumor cytosol estradiol-receptor complex has a Ka of 1.7 X 10(9) M-1 and 9.2 X 10(-10) M binding sites. Competition for the tritiated 17beta-estradiol binding sites in the renal tumor was similar to that in the uterus with respect to estrogenic compounds. Nonestrogenic steroids exhibited minimal competition at the same concentrations or higher. Substitution in the ring structure, particularly in position 3 of the phenolic A-ring, resulted in a considerable loss in the ability of such compounds to compete for these receptors. Aniestrogens were effective competitors for these estrogen receptors only at higher concentrations relative to the tritiated estradiol.

Estrogen-dependent renal adenocarcinoma and normal proximal tubules of the hamster kidney exhibit junctional differences. Although both cell types possess gap junctions, the neoplastic cells have in addition a cytoplasmic configuration of gap-junctional membrane (annular nexuses) not found in the kidneys of untreated or estrogenized hamsters or in the nontumorous kidney adjacent to the adenocarcinoma. The presence of these unique structures in the renal tumor and its abdominal metastases was demonstrated by electron microscopy with the use of lanthanum impregnation. A possible correlation between these structures and the estrogen sensitivity of the kidney neoplasm is made.

Chronic natural or synthetic estrogen treatment of Syrian golden hamsters leads to the development of malignant renal neoplasms. In the present study, morphological and immunohistochemical studies were performed to further characterize the estrogen-induced hamster renal tumors. The neoplasms were composed of two distinct cell populations: a large-cell component that appeared highly epithelial, and a poorly differentiated small-cell component. Importantly, both cell types had epithelial characteristics, since they contained desmosomes at their cell surfaces. However, the large-cell component possessed additional epithelial features such as microvilli, intracytoplasmic lumens, and cilia. Comparative studies of renal tumors and developing renal tissue from fetal and newborn hamsters revealed remarkable histological similarities. Morphologically, the large tumor cells resembled early metanephric tubules and the small tumor cells were very similar to the blastemal cells of the developing kidney. The earliest tumor foci were found after 4.5 months of treatment. They were consistently found in the kidney interstitium in proximity to large arteries. Immunohistochemical staining for intermediate filaments in developing fetal and newborn kidneys demonstrated cytokeratin in renal tubules, desmin in blastemal cells, and vimentin in stromal cells. Estrogen-induced renal tumor cells uniquely possessed reactivity for all three intermediate filaments, clearly demonstrating their epithelial and mesenchymal characteristics. Based on their morphological resemblance to developing embryonic kidney cells and the presence of both epithelial and mesenchymal intermediate filaments, our findings provide strong evidence that the cell of origin of this malignant tumor is a precursor cell that is committed to an epithelial differentiation pathway.