STAT3 as a target for sensitizing prostate cancer cells to irradiation.

Radioresistance of prostate cancer (PCa) is a major factor leading to local failure of radiotherapy. STAT3 is an oncogenic protein that was recently found to be activated in PCa tumors. This study aimed to investigate the radiosensitization effect of targeting STAT3 in PCa tumors. Here, the radiosensitization effect of STAT3 blockade was investigated by clonogenic assay, flow cytometry and western blot analysis in human PCa cells in vitro and in vivo. We demonstrated that STAT3 blockade with a STAT3 inhibitor or siRNA increased the radiosensitivity of PCa cells and that radiation together with STAT3 blockade induced more apoptosis and double-strand breaks (DSBs) than radiation alone in LNCaP cells. In addition, radiation induced STAT3 activation and survivin expression in PCa cells, which was inhibited by STAT3 blockade. Transfection with survivin cDNA attenuated the radiosensitization effect of STAT3 blockade. These effects were further confirmed by in vivo studies, which showed that the STAT3 inhibitor enhanced the treatment efficacy of radiation on LNCaP xenografts with decreased STAT3 activation and survivin expression. These findings suggest that STAT3 blockade radiosensitizes PCa cells through regulation of survivin. Thus, our study has revealed STAT3 as a potential sensitizer for irradiation in PCa cells. Its clinical application as an adjuvant in radiotherapy of PCa should be explored in the future.

Laparoscopic TME associated with neoadjuvant chemoradiation towards aggressive colorectal cancer.

OBJECTIVE: This study aims to investigate the clinical synchronization of the neoadjuvant chemoradiation (NC) and the laparoscopic total mesorectal excision (TME) in the treatment of locally aggressive colorectal cancer (LACC). METHODS: 92 LACC patients were selected for the research, among who 46 cases, who were performed the synchronized NC, were divided into the treatment group, after having rest for 4-6 weeks after the treatment, the 40 patients of the treatment group, who were performed the laparoscopic surgery, formed the laparoscopy group. The rest 46 patients were divided into the control group, who were performed the conventional treatment. The intraoperative conditions, postoperative recoveries, postoperative complications and recurrence rates of the two groups were compared. RESULTS: The stage-declining rate of the treatment group was 67.3%, and the surgical resection rate, anal preservation rate and postoperative complications were 86.9%, 69.6% and 26%, respectively, which were significantly higher than the control group; while the long-term recurrence rate significantly decreased to 21.7%, and the difference was statistically significant (P<0.05). CONCLUSION: The NC could effectively achieve the stage-declining purpose against the LACC, improve the resection rate and reduce the postoperative recurrence rate.

Gastric cancer differentiation using Fourier transform near-infrared spectroscopy with unsupervised pattern recognition.

The manuscript has investigated the application of near-infrared (NIR) spectroscopy for differentiation gastric cancer. The 90 spectra from cancerous and normal tissues were collected from a total of 30 surgical specimens using Fourier transform near-infrared spectroscopy (FT-NIR) equipped with a fiber-optic probe. Major spectral differences were observed in the CH-stretching second overtone (9000-7000 cm(-1)), CH-stretching first overtone (6000-5200 cm(-1)), and CH-stretching combination (4500-4000 cm(-1)) regions. By use of unsupervised pattern recognition, such as principal component analysis (PCA) and cluster analysis (CA), all spectra were classified into cancerous and normal tissue groups with accuracy up to 81.1%. The sensitivity and specificity was 100% and 68.2%, respectively. These present results indicate that CH-stretching first, combination band and second overtone regions can serve as diagnostic markers for gastric cancer.

[Growth hormone enhances regeneration of cavernous nerves after their transplantation in rats].

OBJECTIVE: To investigate the effect of growth hormone (GH) on penile erection after reconstruction of cavernous nerves using sural nerve as an interposition nerve graft in rats. METHODS: Twenty-four male Sprague-Dawley rats (3-4 ms of age and 300-400 g in weight) were randomly divided into 2 groups: nerve graft group and GH group, each electrostimulated to determine the erectile potency 2 and 4 months after nerve graft (followed by hypodermic GH injection). The nNOS-positive nerve fibers in the corpora cavemosa were examined by streptavidin-peroxidase immunohistochemistry technique (SP method). Image analysis was used to calculate the area stained in pixel. RESULTS: Electrostimulation at 2 months produced 31.25% of erections in the GH group but none in the grafted rats. There was a significant difference in the erection rate produced by electrostimulation between the two groups at 2 months (P < 0.05). The pixel of the expression of nNOS-positive nerve fibers in the GH group (38971 +/- 7692) was also greater than that of the graft group (16538 +/- 3179, P < 0.05). At 4 months, 43.75% of the graft group and 75% of the GH group produced erections upon electrostimulation, with no significant difference between the two groups (P > 0.05). The pixels of the expression of nNOS-positive nerve fibers were 79276 +/- 12,021 and 91348 +/- 18965, respectively (P > 0.05). CONCLUSION: GH can accelerate the regeneration of cavernous nerves after bilateral nerve grafting, and GH administration may present a new physiological approach to the treatment of erectile dysfunction after radical pelvic surgery.

[Effects on erectile function of transplanted major pelvic ganglion into the corpus cavernosum of adult rats with bilateral cavernous nerve injury].

OBJECTIVE: To investigate the effects on erectile function of transplanted major pelvic ganglion into the corpus cavernosum of adult male rats undergoing transection of bilateral cavernous nerves. METHODS: Twenty-six male Sprague-Dawley rats (3 - 4 month-old and 300 - 400 g/each) were divided into 2 groups: experimental group (transection of bilateral cavernous nerves and transplantation of left ganglion into left crus of penis, n = 16) and control group (transection of bilateral cavernous nerves only, n = 10). Erectile function was measured by injecting APO, and intracavernous pressure was measured 1 and 3 months afterwards by electric-stimulating the right major pelvic ganglion or the left crus. Half animals in each group were sacrificed 1 and 3 months afterwards for detecting nNOS-containing nerve fibers of corpus cavernosum. Electron microscopy of the implanted area was performed to assess neuronal survival. RESULTS: Both of the two groups have no erectile response to APO injection. Electrostimulation on the right major pelvic ganglion and left crus failed to produce erection in experimental group. The mean pressure changes in the two groups, measured by stimulating the left crus, were (9.41 +/- 3.20) and (4.16 +/- 2.58) cmH(2)O 1 month afterwards, and (13.67 +/- 4.18) and (5.09 +/- 2.74) cmH(2)O 3 months afterwards, respectively (P < 0.05). An increased number of nNOS-containing nerve fibers in left crus was detected in experimental group 1 and 3 months later, compared with control one (218.7 +/- 24.5, 18.0 +/- 3.7; 183.2 +/- 19.7, 19.0 +/- 3.8; P < 0.05). Ultrastructure examination by transmission electron microscope confirmed the survival of the implanted ganglion. CONCLUSION: Major pelvic ganglion can survive in the corpus cavernosum, and it has significant effects on the number of nNOS-containing nerve fibers and the alteration of intracavernous pressure.