Impact of STAT-signaling pathway on cancer-associated fibroblasts in colorectal cancer and its role in immunosuppression.

Colorectal cancer (CRC) remains one of the most commonly diagnosed and deadliest types of cancer worldwide. CRC displays a desmoplastic reaction (DR) that has been inversely associated with poor prognosis; less DR is associated with a better prognosis. This reaction generates excessive connective tissue, in which cancer-associated fibroblasts (CAFs) are critical cells that form a part of the tumor microenvironment. CAFs are directly involved in tumorigenesis through different mechanisms. However, their role in immunosuppression in CRC is not well understood, and the precise role of signal transducers and activators of transcription (STATs) in mediating CAF activity in CRC remains unclear. Among the myriad chemical and biological factors that affect CAFs, different cytokines mediate their function by activating STAT signaling pathways. Thus, the harmful effects of CAFs in favoring tumor growth and invasion may be modulated using STAT inhibitors. Here, we analyze the impact of different STATs on CAF activity and their immunoregulatory role.

Postmenopause is associated with recurrence of differentiated papillary thyroid carcinoma.

UNLABELLED: Differentiated papillary thyroid carcinoma (D-PTC) is the most common malignancy arising in the thyroid gland. There are gender differences in the incidence of PTC being mainly observed in females. Low-risk groups consisted of men younger than 40-year-old and women younger than 50-year-old, whereas the high-risk group are older patients. We believe that age is not enough to explain the clinical course of this neoplasm and hypothesize that aggressive behavior of D-PTC may be correlated with hormonal status. Studies that support this idea showed that the follicular neoplastic cells had higher estrogen receptor-alpha in premenopausal (28.1+/-4.5) than in postmenopausal women (14.2+/-2.9). According to author's prior observations, there are evidences correlating recurrence of D-PTC with postmenopause in women. Postmenopause status is characterized by estrogen decrease and FSH increases both associated with EGFR activation. Previous observations identified EGFR over-expression in D-PTC of postmenopause when compared with premenopausal ladies. CONCLUSIONS: Postmenopause is an adverse factor for tumor evolution in women with D-PTC and is associated with EGFR expression. It's introduction in thyroid tumor stratification could be a fine tuning in predicting papillary thyroid carcinoma behavior.

Pleomorphic leiomyosarcoma of the adrenal gland with osteoclast-like giant cells.

Pleomorphic leiomyosarcoma (PLMS) of the adrenal gland is a rare tumor in an unusual location. A primary PLMS of the left adrenal gland is reported in a 59-yr-old Mexican woman who presented progressive flank pain and weight loss. The tumor measured 16 cm in diameter, showed markedly pleomorphic and osteoclast-like giant cells, necrosis, and high mitotic activity (average 15 per 10 high-power fields). The phenotype was supported by light microscopy and corroborated by immunohistochemistry. The neoplastic cells were strongly positive for muscle-specific actin, desmin, vimentin, and p53. They were negative for CD34, HMB45, estrogen receptors, and S-100 protein. The percentage of Ki-67 positive neoplastic cells was 7.6%. DNA content analysis by flow cytometry showed that tumor was diploid, with a high level of apoptosis. Extra-adrenal primary sites of origin were clinically excluded. The patient developed local recurrence and liver metastases 12 mo after initial treatment. She then received adjuvant chemotherapy and radiotherapy and the metastasis was resected. Twenty-four months later, she is alive with no evidence of disease. This is the second case of adrenal PLMS reported. This case exhibited a high histologic grade, aggressive behavior, and p53 overexpression, but diploid DNA content.