High mitochondrial content is associated with breast cancer aggressiveness.

Mitochondria are relevant for cancer initiation and progression. Antibodies against mitochondrially encoded cytochrome c oxidase II (MTCO2), targeting a mitochondria specific epitope, can be used to quantitate the mitochondria content of tumor cells. The present study evaluated the impact of the cellular mitochondrial content on the prognosis of patients with breast cancer using immunohistochemical analysis on 2,197 arrayed breast cancer specimens. Results were compared with histological tumor parameters, patient overall survival, tumor cell proliferation using Ki67 labeling index (Ki67LI) and various other molecular features. Tumor cells exhibited stronger MTCO2 expression than normal breast epithelial cells. MTCO2 immunostaining was largely absent in normal breast epithelium, but was observed in 71.9% of 1,797 analyzable cancer specimens, including 34.6% tumors with weak expression, 22.3% with moderate expression and 15.0% with strong expression. High MTCO2 expression was significantly associated with advanced tumor stage, high Bloom-Richardson-Elston/Nottingham (BRE) grade, nodal metastasis and shorter overall survival (P<0.0001 each). In multivariate analysis, MTCO2 expression did not provide prognostic information independent of BRE grade, pathological tumor and pathological lymph node status. Additionally, significant associations were observed for high MTCO2 expression and various molecular features, including high Ki67LI, amplifications of HER2, MYC, CCND1 and MDM2, deletions of PTEN, 8p21 and 9p, low estrogen receptor expression (P<0.0001 each) and progesterone receptor expression (P<0.0001). The present study demonstrated that high MTCO2 expression was strongly associated with a poor prognosis and unfavorable phenotypical and molecular tumor features in patients with breast cancer. This suggests that the mitochondrial content may have a pivotal role in breast cancer progression.

MUC5AC expression is linked to mucinous/endometroid subtype, absence of nodal metastasis and mismatch repair deficiency in ovarian cancer.

Mucin 5AC (MUC5AC) is a secreted gel-forming mucin which is expressed by mucus producing cells of several organs but can also be found in cancer cells of the ovary, pancreas, and gastrointestinal tract. This study aimed to characterize the expression of MUC5AC and its potential prognostic implications in different ovarian cancer subtypes. MUC5AC expression was analyzed by immunohistochemistry on a tissue microarray containing 603 ovarian cancers. MUC5AC was commonly expressed in mucinous (27/36; 75%) and endometrioid (12/39; 31%) carcinomas, whereas malignant mixed Mullerian tumors (2/27; 7%), high-grade serous (20/373; 5%) and clear cell carcinomas (1/28; 4%) were only rarely MUC5AC positive and also showed lower expression levels. MUC5AC positive endometroid carcinomas and high-grade serous carcinomas lacked lymph node metastases (p = 0.0495 and p = 0.0216) suggesting a more favorable prognosis. Deficient mismatch repair (dMMR), associated with a favorable prognosis in different cancer types, was found in 4/39 (10%) MUC5AC positive cancers but in only 5/375 (1%) of MUC5AC negative cancers (p = 0.0052). In subgroup analyses MUC5AC positive endometroid carcinomas more frequently showed dMMR (4/10; 40%) as opposed to MUC5AC negative endometroid carcinomas (3/23; 13%; p = 0.0932). In summary, the results of our study show that MUC5AC expression is associated with mucinous and endometrioid ovarian carcinomas, lack of nodal metastases and dMMR. MUC5AC expressing ovarian cancers should be evaluated for dMMR.

High homogeneity of MMR deficiency in ovarian cancer.

OBJECTIVE: Mismatch repair (MMR) deficiency and Bethesda panel microsatellite instability (MSI) are increasingly analyzed to identify tumors that might benefit from immune checkpoint inhibitors, but tumor heterogeneity is a potential obstacle for such analyses. In ovarian cancer, data on intratumoral heterogeneity of MMR deficiency/MSI are lacking. METHODS: N = 582 ovarian cancers were screened for MMR deficiency by immunohistochemistry (IHC) on a tissue microarray. 10 cases suspect for MMR deficiency were identified among 478 interpretable cancers and repeated IHC on large sections combined with polymerase chain reaction (PCR)-based MSI analysis validated MMR deficiency/MSI in 9 of these tumors. RESULTS: MMR deficiency/MSI was predominantly seen in endmetrioid cancers (8 of 35, 23%) and also in 1 of 358 serous carcinomas (0.3%), but was absent in 34 mucinous carcinomas, 23 clear cell carcinomas, 17 malignant mixed Mullerian tumors (carcinosarcomas), and 11 mixed carcinomas. MMR deficiency involed protein loss of PMS2/MLH1 in 6 cases and of MSH2 and/or MSH6 in 3 cases. 7 MMR deficient cancers were MSI-high (all endometrioid), one was MSI-low (endometrioid) and one cancer with unequivocal MMR protein loss exhibited microsatellite stability (serous). MLH1 promotor methylation was observed in 4 of 5 endometrioid cancers with MLH1 protein loss. Immunostaining of all available cancer-containing tissue blocks (n = 114) of tumors with confirmed MMR deficiency/MSI revealed uniform MMR status throughout the entire tumor mass. CONCLUSIONS: Our data show that MSI is present in a substantial proportion of endometrioid ovarian cancers but can also occur in other tumor subtypes. MMR deficiency/MSI typically involves the entire tumor mass, suggesting that MMR inactivation occurs early in tumorigenesis in a subset of ovarian cancers.

A shift from membranous and stromal syndecan-1 (CD138) expression to cytoplasmic CD138 expression is associated with poor prognosis in breast cancer.

Syndecan-1 (CD138) is a transmembrane proteoglycan expressed in normal and malignant tissues. It is of interest because of a possible prognostic effect in tumors and as a target for Indatuximab, a monoclonal antibody coupled to a cytotoxic agent. To assess the prognostic role of CD138 expression in breast cancer (BCa), a tissue microarray containing 1535 BCa specimens was analyzed by immunohistochemistry. Cytoplasmic, membranous, and stromal CD138 staining was separately analyzed. In normal breast tissue, CD138 staining was limited to epithelial cell membranes. In cancers, membranous staining tended to become weaker or even disappeared (38.3% of cancers with absence of membranous staining) but cytoplasmic and stromal staining newly appeared in 29.7% and 58.1% of cancers. Loss of membranous epithelial CD138 staining as well as presence of cytoplasmic and stromal CD138 positivity were-to a variable degree-associated with high pT, high grade, nodal metastasis, estrogen receptor-negative, progesterone receptor-negative, human epidermal growth factor receptor 2+, and poor overall patient survival. A combined analysis of epithelial and stromal CD138 expression revealed a link to overall patient survival (P < .0001) with best prognosis for patients with stromal positivity and absence of cytoplasmic staining, the worst prognosis for cancers with cytoplasmic staining and stromal negativity and intermediate prognosis for patients having either cytoplasmic staining or stromal negativity. In multivariate analyses, CD138 was not independent of established prognostic features. In summary, these data reveal a compartment depending prognostic effect of CD138 expression in BCa with cytoplasmic positivity being linked to aggressive cancer and stromal CD138 being linked to a more favorable prognosis.

A Randomized Trial of Lymphadenectomy in Patients with Advanced Ovarian Neoplasms.

BACKGROUND: Systematic pelvic and paraaortic lymphadenectomy has been widely used in the surgical treatment of patients with advanced ovarian cancer, although supporting evidence from randomized clinical trials has been limited. METHODS: We intraoperatively randomly assigned patients with newly diagnosed advanced ovarian cancer (International Federation of Gynecology and Obstetrics stage IIB through IV) who had undergone macroscopically complete resection and had normal lymph nodes both before and during surgery to either undergo or not undergo lymphadenectomy. All centers had to qualify with regard to surgical skills before participation in the trial. The primary end point was overall survival. RESULTS: A total of 647 patients underwent randomization from December 2008 through January 2012, were assigned to undergo lymphadenectomy (323 patients) or not undergo lymphadenectomy (324), and were included in the analysis. Among patients who underwent lymphadenectomy, the median number of removed nodes was 57 (35 pelvic and 22 paraaortic nodes). The median overall survival was 69.2 months in the no-lymphadenectomy group and 65.5 months in the lymphadenectomy group (hazard ratio for death in the lymphadenectomy group, 1.06; 95% confidence interval [CI], 0.83 to 1.34; P = 0.65), and median progression-free survival was 25.5 months in both groups (hazard ratio for progression or death in the lymphadenectomy group, 1.11; 95% CI, 0.92 to 1.34; P = 0.29). Serious postoperative complications occurred more frequently in the lymphadenectomy group (e.g., incidence of repeat laparotomy, 12.4% vs. 6.5% [P = 0.01]; mortality within 60 days after surgery, 3.1% vs. 0.9% [P = 0.049]). CONCLUSIONS: Systematic pelvic and paraaortic lymphadenectomy in patients with advanced ovarian cancer who had undergone intraabdominal macroscopically complete resection and had normal lymph nodes both before and during surgery was not associated with longer overall or progression-free survival than no lymphadenectomy and was associated with a higher incidence of postoperative complications. (Funded by Deutsche Forschungsgemeinschaft and the Austrian Science Fund; LION ClinicalTrials.gov number, NCT00712218.).

Patterns of Chromosomal Abnormalities that Can Improve Diagnosis of Uterine Smooth Muscle Tumors.

BACKGROUND/AIM: Compared to leiomyomas, smooth muscle tumors of uncertain malignant potential (STUMP), and leiomyosarcomas (LMS) originating from the Muellerian duct are very rare. Their molecular pathogenesis remains poorly understood. The present article aims at performing genetic analyses of these tumors that may help assist histopathological examination. MATERIALS AND METHODS: Ten tumors (four STUMP and six LMS) were investigated by copy number arrays. RESULTS: Two tumors, both classified as STUMP were shown to carry MED12 mutations with one of them presenting with a detectable copy number alteration. All other tumors had multiple copy number changes with a clear predominance of losses. Five chromosomal arms (1p, 13q, 14q, 16q, 22q) were affected by overlapping lost segments in at least four tumors including two cases with biallelic losses of the retinoblastoma gene locus. CONCLUSION: Besides the general presence of copy number alterations and particular genetic alterations, heterogeneity and ongoing karyotypic evolution indicate malignancy or approaching malignancy.