fit table to page latex
\documentclass{article}
\usepackage{adjustbox} %this
\usepackage{lipsum}% example text
\begin{document}
\lipsum
\begin{table}[ht]
\centering
\begin{adjustbox}{width=1\textwidth} %...this...
\small
\begin{tabular}{rlrrrrrrr}
\hline
& X & MASHvstRap & MASHvsBEEML & tRapvsBEEML & frequency & Mash\_mean & BEEML\_mean & tRap\_mean \\
\hline
1 & ETS & 8.95e-04 & 7.35e-04 & 4.78e-06 & 10 & 0.52 & 0.67 & 0.30 \\
11 & ZnF\_C2H2 & 7.08e-21 & 2.09e-02 & 1.70e-26 & 54 & 0.55 & 0.64 & 0.25 \\
10 & Zn2Cys6 & 4.94e-04 & 5.50e-02 & 3.52e-06 & 17 & 0.38 & 0.61 & 0.13 \\
8 & IRF & 1.16e-06 & 6.65e-02 & 5.54e-08 & 10 & 0.52 & 0.62 & 0.28 \\
2 & FH & 1.27e-05 & 8.61e-02 & 5.20e-07 & 10 & 0.53 & 0.66 & 0.27 \\
3 & HLH & 2.49e-05 & 1.31e+00 & 4.27e-05 & 13 & 0.61 & 0.74 & 0.26 \\
4 & HMG & 8.73e-33 & 1.41e+00 & 3.49e-08 & 44 & 0.55 & 0.48 & 0.12 \\
12 & ZnF\_C4 & 2.92e-06 & 1.92e+00 & 1.03e-07 & 10 & 0.66 & 0.73 & 0.27 \\
9 & unknown & 3.15e-27 & 1.96e+00 & 5.38e-21 & 121 & 0.44 & 0.49 & 0.16 \\
5 & Homeo & 1.69e-164 & 6.26e+00 & 2.35e-75 & 158 & 0.72 & 0.73 & 0.17 \\
7 & Homeo, POU & 3.12e-12 & 7.36e+00 & 5.21e-12 & 11 & 0.69 & 0.70 & 0.18 \\
6 & Homeo & 9.82e-13 & 9.73e+00 & 1.21e-05 & 19 & 0.67 & 0.65 & 0.14 \\
\hline
\end{tabular}
\end{adjustbox} %...and finally, this!
\caption{Paired t-test of most common TF families for Pearson Correlations}
\end{table}
\lipsum
\end{document}