Differential expression of metallothionein and p21 in gastric cancer and some precursor lesions

OBJECTIVE

Gastric cancer (GC) is a heterogeneous disease with molecular diversity between and within tumors; therefore, searching for altered genes within this cancer is mandatory to reach the proper individualized targeted therapy. Expressions of Metallothionein (MT) and p21 are not uniform in various types of cancers and their predictive value in GC is controversial. This study aimed to assess the role of MT and p21 in intestinal-type GC and some of its precursor lesions.

MATERIALS AND METHODS

Immunohistochemical staining for MT and p21 was applied on paraffin blocks belonging to 30 GCs and 51 benign gastric lesions/precancerous lesions [33 chronic gastritis and 18 chronic gastritis with gastric intestinal metaplasia (GIM)]; 27 of them were associated with H. pylori infection.

RESULTS

MT expression was dramatically increased while p21 expression was dramatically decreased from chronic gastritis to GIM to GC. In precancerous lesions, H. pylori-positive cases had significantly higher MT expression and lower p21 expression compared to H. pylori-negative cases. In GCs, decreased expression of both MT and p21 was associated with high-grade and advanced-stage cancers.

CONCLUSIONS

Both MT and p21 may have a role in the development and progression of GC, and both proteins may be useful for selecting targeted therapy for GC patients.

Implication of miRNA-153 on PTEN expression in prostatic adenocarcinoma

OBJECTIVE

A little is known about the role of miRNA-153 expression in prostate cancer (PCa), in this study we aimed to determine the prognostic value of miRNA-153 and PTEN expression in PCa, by correlating their expression with Gleason patterns, Gleason scores, and Grade groups.

PATIENTS AND METHODS

 In situ hybridization for miRNA-153 and immunohistochemical staining for PTEN were applied on microarray sections of 80 PCa, with different Gleason grades, and 20 benign prostate hyperplasia (BPH) cases.

RESULTS

We found that miRNA-153 expression was significantly higher and PTEN was significantly lower in PCa compared to BPH. In PCa, high miRNA-153 expression and loss of PTEN expression were associated significantly with higher Gleason patterns, higher Gleason scores, and higher Grade groups. The expression of miRNA-153 showed a significant inverse correlation with PTEN expression.

CONCLUSIONS

Increased miRNA-153 expression and lost PTEN expression in PCa may provide information on their role in the progression of this cancer, suggesting that miRNA-153 could affect PTEN directly in prostatic neoplastic and hyperplastic lesions, and therefore miRNA-153 can be considered a new tool to improve the treatment efficacy and prognosis of PCa patients.